Form N-Q

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, DC 20549

FORM N-Q


QUARTERLY SCHEDULE OF PORTFOLIO HOLDINGS OF REGISTERED MANAGEMENT INVESTMENT COMPANY

Investment Company Act file number         811-6622         

        Nuveen Select Tax-Free Income Portfolio 2         
(Exact name of registrant as specified in charter)


        333 West Wacker Drive, Chicago, Illinois 60606         
(Address of principal executive offices) (Zip code)


Jessica R. Droeger—Vice President and Secretary
        333 West Wacker Drive, Chicago, Illinois 60606         
(Name and address of agent for service)

Registrant's telephone number, including area code:         312-917-7700        

Date of fiscal year end:            3/31          

Date of reporting period:         6/30/06         

Form N-Q is to be used by management investment companies, other than small business investment companies registered on Form N-5 (§§ 239.24 and 274.5 of this chapter), to file reports with the Commission, not later than 60 days after the close of the first and third fiscal quarters, pursuant to rule 30b1-5 under the Investment Company Act of 1940 (17 CFR 270.30b1-5). The Commission may use the information provided on Form N-Q in its regulatory, disclosure review, inspection, and policymaking roles.

A registrant is required to disclose the information specified by Form N-Q, and the Commission will make this information public. A registrant is not required to respond to the collection of information contained in Form N-Q unless the Form displays a currently valid Office of Management and Budget (“OMB”) control number. Please direct comments concerning the accuracy of the information collection burden estimate and any suggestions for reducing the burden to the Secretary, Securities and Exchange Commission, 450 Fifth Street, NW, Washington, DC 20549-0609. The OMB has reviewed this collection of information under the clearance requirements of 44 U.S.C. § 3507.

Item 1. Schedule of Investments

    Portfolio of Investments (Unaudited)             
    Nuveen Select Tax-Free Income Portfolio 2 (NXQ)             
    June 30, 2006             
Principal        Optional Call         
Amount (000)    Description    Provisions (1)    Ratings (2)    Value 
    Arkansas – 1.7%             
$          1,000    Fort Smith, Arkansas, Water and Sewer Revenue Refunding and Construction Bonds, Series 2002A,    10/11 at 100.00    AAA   $   1,032,440 
     5.000%, 10/01/19 – FSA Insured             
1,205    Sebastian County Health Facilities Board, Arkansas, Hospital Revenue Improvement Bonds, Sparks    11/11 at 101.00    Baa2    1,206,072 
     Regional Medical Center, Series 2001A, 5.250%, 11/01/21             
2,000    University of Arkansas, Fayetteville, Various Facilities Revenue Bonds, Series 2002, 5.000%,    12/12 at 100.00    Aaa    2,030,080 
     12/01/32 – FGIC Insured             
4,205    Total Arkansas            4,268,592 
    California – 7.4%             
1,000    Alameda Corridor Transportation Authority, California, Subordinate Lien Revenue Bonds, Series    10/17 at 100.00    AAA    759,030 
     2004A, 0.000%, 10/01/25 – AMBAC Insured             
3,325    California Department of Water Resources, Power Supply Revenue Bonds, Series 2002A,    5/12 at 101.00    A2    3,683,269 
     6.000%, 5/01/14             
500    California State Public Works Board, Lease Revenue Refunding Bonds, Community Colleges    12/08 at 101.00    A–    514,100 
     Projects, Series 1998A, 5.250%, 12/01/16             
2,000    California State Public Works Board, Lease Revenue Refunding Bonds, Various University of    No Opt. Call    Aa2    2,152,060 
     California Projects, Series 1993A, 5.500%, 6/01/14             
190    California, General Obligation Bonds, Series 1997, 5.000%, 10/01/18 – AMBAC Insured    10/07 at 101.00    AAA    193,108 
    California, General Obligation Bonds, Series 1997:             
2,105     5.000%, 10/01/18 (Pre-refunded 10/01/07) – AMBAC Insured    10/07 at 101.00    AAA    2,158,320 
205     5.000%, 10/01/18 (Pre-refunded 10/01/07) – AMBAC Insured    10/07 at 101.00    AAA    210,193 
2,500    California, General Obligation Bonds, Series 2005, 5.000%, 3/01/31    3/16 at 100.00    A    2,529,475 
500    Contra Costa County, California, Certificates of Participation Refunding, Merrithew Memorial    11/07 at 102.00    AAA    518,745 
     Hospital Replacement, Series 1997, 5.375%, 11/01/17 – MBIA Insured             
500    Contra Costa Water District, California, Water Revenue Refunding Bonds, Series 1997H,    10/07 at 100.00    AA    504,950 
     5.000%, 10/01/17             
3,200    Golden State Tobacco Securitization Corporation, California, Tobacco Settlement Asset-Backed    6/13 at 100.00    BBB    3,584,544 
     Bonds, Series 2003A-1, 6.750%, 6/01/39             
1,750    Tobacco Securitization Authority of Northern California, Tobacco Settlement Asset-Backed    6/15 at 100.00    BBB    1,765,260 
     Bonds, Series 2005A-1, 5.500%, 6/01/45             
17,775    Total California            18,573,054 
    Colorado – 9.4%             
1,300    Colorado Health Facilities Authority, Revenue Bonds, Catholic Health Initiatives, Series    3/12 at 100.00    AA    1,370,642 
     2002A, 5.500%, 3/01/22             
1,700    Colorado Health Facilities Authority, Revenue Bonds, Catholic Health Initiatives, Series    3/12 at 100.00    AA (3)    1,819,204 
     2002A, 5.500%, 3/01/22 (ETM)             
3,185    Denver City and County, Colorado, Airport System Revenue Bonds, Series 1991D, 7.750%, 11/15/13    No Opt. Call    A    3,565,830 
     (Alternative Minimum Tax)             
5,000    Denver City and County, Colorado, Airport System Revenue Refunding Bonds, Series 2001A,    11/11 at 100.00    AAA    5,283,950 
     5.625%, 11/15/17 – FGIC Insured (Alternative Minimum Tax)             
1,555    Denver City and County, Colorado, Airport System Revenue Refunding Bonds, Series 2001, 5.500%,    11/11 at 100.00    AAA    1,647,678 
     11/15/16 – FGIC Insured             
3,000    Denver Convention Center Hotel Authority, Colorado, Senior Revenue Bonds, Convention Center    12/13 at 100.00    AAA    3,155,820 
     Hotel, Series 2003A, 5.000%, 12/01/23 (Pre-refunded 12/01/13) – XLCA Insured             
2,000    Denver Convention Center Hotel Authority, Colorado, Senior Revenue Bonds, Convention Center    11/16 at 100.00    AAA    1,942,820 
     Hotel, Series 2006, 4.750%, 12/01/35 – XLCA Insured             
5,000    E-470 Public Highway Authority, Colorado, Senior Revenue Bonds, Series 2000B, 0.000%,    No Opt. Call    AAA    2,038,350 
     9/01/24 – MBIA Insured             
5,000    E-470 Public Highway Authority, Colorado, Senior Revenue Bonds, Series 2000B, 0.000%, 9/01/28    9/10 at 31.42    AAA    1,324,250 
     (Pre-refunded 9/01/10) – MBIA Insured             
250    Northwest Parkway Public Highway Authority, Colorado, Revenue Bonds, Senior Series 2001A,    6/11 at 102.00    AAA    257,625 
     5.250%, 6/15/41 – FSA Insured             
1,100    University of Colorado Hospital Authority, Revenue Bonds, Series 2001A, 5.600%, 11/15/31    11/11 at 100.00    Baa1    1,130,437 
29,090    Total Colorado            23,536,606 
    District of Columbia – 0.4%             
500    District of Columbia, Hospital Revenue Refunding Bonds, Medlantic Healthcare Group, Series    8/06 at 102.00    AAA    511,065 
     1996A, 5.750%, 8/15/16 – MBIA Insured (ETM)             
500    Washington Convention Center Authority, District of Columbia, Senior Lien Dedicated Tax    10/08 at 101.00    AAA    511,450 
     Revenue Bonds, Series 1998, 5.000%, 10/01/21 – AMBAC Insured             
1,000    Total District of Columbia            1,022,515 
    Florida – 1.9%             
1,500    Jacksonville, Florida, Guaranteed Entitlement Revenue Refunding and Improvement Bonds, Series    10/12 at 100.00    AAA    1,543,515 
     2002, 5.000%, 10/01/21 – FGIC Insured             
2,500    JEA, Florida, Electric System Revenue Bonds, Series 2006-3A, 5.000%, 10/01/41 – FSA Insured    4/15 at 100.00    AAA    2,531,825 
625    Miami-Dade County Expressway Authority, Florida, Toll System Revenue Refunding Bonds, Series    7/11 at 101.00    Aaa    639,575 
     2001, 5.125%, 7/01/29 – FGIC Insured             
4,625    Total Florida            4,714,915 
    Hawaii – 0.4%             
1,100    Hawaii, Certificates of Participation, Kapolei State Office Building, Series 1998A, 5.000%,    11/08 at 101.00    AAA    1,128,072 
     5/01/17 – AMBAC Insured             
    Illinois – 13.9%             
1,230    Chicago Metropolitan Housing Development Corporation, Illinois, FHA-Insured Section 8 Assisted    7/06 at 100.00    AA    1,231,599 
     Housing Development Revenue Refunding Bonds, Series 1992, 6.800%, 7/01/17             
1,665    Chicago, Illinois, Third Lien General Airport Revenue Bonds, O’Hare International Airport,    1/16 at 100.00    AAA    1,686,995 
     Series 2005A, 5.000%, 1/01/33 – FGIC Insured             
250    Illinois Development Finance Authority, Economic Development Revenue Bonds, Latin School of    8/08 at 100.00    Baa2 (3)    255,897 
     Chicago, Series 1998, 5.200%, 8/01/11 (Pre-refunded 8/01/08)             
600    Illinois Educational Facilities Authority, Student Housing Revenue Bonds, Educational    5/12 at 101.00    Baa3    641,562 
     Advancement Foundation Fund, University Center Project, Series 2002, 6.000%, 5/01/22             
2,185    Illinois Finance Authority, Revenue Bonds, YMCA of Southwest Illinois, Series 2005, 5.000%,    9/15 at 100.00    AA    2,198,438 
     9/01/31 – RAAI Insured             
2,255    Illinois Health Facilities Authority, Revenue Bonds, Lake Forest Hospital, Series 2002A,    7/12 at 100.00    A–    2,429,266 
     6.250%, 7/01/22             
1,055    Illinois Health Facilities Authority, Revenue Bonds, Loyola University Health System, Series    7/11 at 100.00    Baa1    1,099,859 
     2001A, 6.125%, 7/01/31             
3,000    Illinois Health Facilities Authority, Revenue Bonds, Rush-Presbyterian St. Luke’s Medical    11/06 at 100.00    AAA    3,002,700 
     Center Obligated Group, Series 1993, 5.250%, 11/15/20 – MBIA Insured             
1,000    Illinois Housing Development Authority, Housing Finance Bonds, Series 2005E, 4.750%, 7/01/30 –    1/15 at 100.00    AAA    985,210 
     FGIC Insured             
5,700    Illinois, Sales Tax Revenue Bonds, First Series 2002, 5.000%, 6/15/22    6/13 at 100.00    AAA    5,861,652 
45    Metropolitan Pier and Exposition Authority, Illinois, Revenue Bonds, McCormick Place Expansion    12/06 at 100.00    A1    45,083 
     Project, Series 1992A, 6.500%, 6/15/22             
7,000    Metropolitan Pier and Exposition Authority, Illinois, Revenue Refunding Bonds, McCormick Place    6/12 at 101.00    AAA    7,211,190 
     Expansion Project, Series 2002B, 5.000%, 6/15/21 – MBIA Insured             
5,045    Sauk Village, Illinois, General Obligation Alternate Revenue Source Bonds, Tax Increment,    12/12 at 100.00    AA    5,098,578 
     Series 2002A, 5.000%, 6/01/22 – RAAI Insured             
    Sauk Village, Illinois, General Obligation Alternate Revenue Source Bonds, Tax Increment,             
    Series 2002B:             
1,060     0.000%, 12/01/17 – RAAI Insured    No Opt. Call    AA    591,130 
1,135     0.000%, 12/01/18 – RAAI Insured    No Opt. Call    AA    597,044 
1,100    Schaumburg, Illinois, General Obligation Bonds, Series 2004B, 5.250%, 12/01/34 – FGIC Insured    12/14 at 100.00    AAA    1,144,341 
1,000    Yorkville, Illinois, General Obligation Debt Certificates, Series 2003, 5.000%, 12/15/21 –    12/11 at 100.00    AA    1,010,200 
     RAAI Insured             
35,325    Total Illinois            35,090,744 
    Indiana – 3.1%             
1,000    Franklin Community Multi-School Building Corporation, Marion County, Indiana, First Mortgage    7/14 at 100.00    AAA    1,027,630 
     Revenue Bonds, Series 2004, 5.000%, 7/15/22 – FGIC Insured             
1,060    Indiana Housing Finance Authority, Single Family Mortgage Revenue Bonds, Series 2002C-2,    7/11 at 100.00    Aaa    1,078,773 
     5.250%, 7/01/23 (Alternative Minimum Tax)             
4,380    Indiana Municipal Power Agency, Power Supply System Revenue Bonds, Series 2002A, 5.125%,    1/12 at 100.00    AAA    4,545,827 
     1/01/21 – AMBAC Insured             
285    St. Joseph County Hospital Authority, Indiana, Revenue Bonds, Memorial Health System, Series    2/08 at 101.00    AAA    275,404 
     1998A, 4.625%, 8/15/28 – MBIA Insured             
750    West Clark 2000 School Building Corporation, Clark County, Indiana, First Mortgage Bonds,    1/15 at 100.00    AAA    771,780 
     Series 2005, 5.000%, 7/15/22 – MBIA Insured             
7,475    Total Indiana            7,699,414 
    Iowa – 2.3%             
1,000    Iowa Tobacco Settlement Authority, Tobacco Asset-Backed Revenue Bonds, Series 2005B, 0.000%,    6/17 at 100.00    BBB    942,460 
     6/01/34             
    Iowa Tobacco Settlement Authority, Tobacco Settlement Asset-Backed Revenue Bonds, Series 2001B:             
1,000     5.300%, 6/01/25 (Pre-refunded 6/01/11)    6/11 at 101.00    AAA    1,056,780 
3,500     5.600%, 6/01/35 (Pre-refunded 6/01/11)    6/11 at 101.00    AAA    3,769,185 
5,500    Total Iowa            5,768,425 
    Kansas – 0.4%             
1,000    Salina, Kansas, Hospital Revenue Bonds, Salina Regional Medical Center, Series 2006,    4/13 at 100.00    A1    938,530 
     4.500%, 10/01/26             
    Louisiana – 2.1%             
2,125    Louisiana Public Facilities Authority, Revenue Bonds, Baton Rouge General Hospital, Series    7/14 at 100.00    AAA    2,210,106 
     2004, 5.250%, 7/01/24 – MBIA Insured             
3,000    Louisiana Public Facilities Authority, Revenue Bonds, Tulane University, Series 2002A, 5.125%,    7/12 at 100.00    AAA    3,051,570 
     7/01/27 – AMBAC Insured             
5,125    Total Louisiana            5,261,676 
    Massachusetts – 3.1%             
3,000    Massachusetts Health and Educational Facilities Authority, Revenue Bonds, Berkshire Health    10/11 at 101.00    BBB+    3,160,830 
     System, Series 2001E, 6.250%, 10/01/31             
2,500    Massachusetts Turnpike Authority, Metropolitan Highway System Revenue Bonds, Senior Series    1/07 at 102.00    AAA    2,515,750 
     1997A, 5.000%, 1/01/37 – MBIA Insured             
2,090    Massachusetts Water Resources Authority, General Revenue Bonds, Series 1993C, 5.250%,    No Opt. Call    AAA    2,227,041 
     12/01/15 – MBIA Insured             
7,590    Total Massachusetts            7,903,621 
    Michigan – 2.0%             
2,900    Michigan State Hospital Finance Authority, Hospital Revenue Refunding Bonds, Trinity Health    12/12 at 100.00    AA–    3,004,835 
     Credit Group, Series 2002C, 5.375%, 12/01/30             
2,000    Plymouth-Canton Community School District, Wayne and Washtenaw Counties, Michigan, Unlimited    5/09 at 100.00    AA    2,019,680 
     Tax General Obligation School Building and Site Bonds, Series 1999, 4.750%, 5/01/18             
4,900    Total Michigan            5,024,515 
    Nevada – 7.5%             
1,500    Clark County, Nevada, General Obligation Bank Bonds, Southern Nevada Water Authority Loan,    6/11 at 100.00    AAA    1,589,340 
     Series 2001, 5.300%, 6/01/19 (Pre-refunded 6/01/11) – FGIC Insured             
500    Clark County, Nevada, Limited Tax General Obligation Las Vegas Convention and Visitors    7/06 at 101.00    AAA    505,595 
     Authority Bonds, Series 1996, 5.500%, 7/01/17 – MBIA Insured             
    Director of Nevada State Department of Business and Industry, Revenue Bonds, Las Vegas             
    Monorail Project, First Tier, Series 2000:             
4,595     0.000%, 1/01/22 – AMBAC Insured    No Opt. Call    AAA    2,134,975 
13,250     5.375%, 1/01/40 – AMBAC Insured    1/10 at 100.00    AAA    13,617,553 
1,100    Nevada, General Obligation Refunding Bonds, Municipal Bond Bank Projects 65 and R-6, Series    5/08 at 100.00    AAA    1,114,069 
     1998, 5.000%, 5/15/22 – MBIA Insured             
20,945    Total Nevada            18,961,532 
    New Jersey – 1.9%             
2,500    New Jersey Health Care Facilities Financing Authority, Revenue Bonds, Somerset Medical Center,    7/13 at 100.00    Baa3    2,542,075 
     Series 2003, 5.500%, 7/01/23             
    Tobacco Settlement Financing Corporation, New Jersey, Tobacco Settlement Asset-Backed Bonds,             
    Series 2003:             
1,000     6.375%, 6/01/32    6/13 at 100.00    BBB    1,086,550 
1,010     6.250%, 6/01/43    6/13 at 100.00    BBB    1,090,073 
4,510    Total New Jersey            4,718,698 
    New Mexico – 2.4%             
    University of New Mexico, FHA-Insured Mortgage Hospital Revenue Bonds, Series 2004:             
555     4.625%, 1/01/25 – FSA Insured    7/14 at 100.00    AAA    544,844 
660     4.625%, 7/01/25 – FSA Insured    7/14 at 100.00    AAA    647,724 
2,000     4.750%, 7/01/27 – FSA Insured    7/14 at 100.00    AAA    1,988,160 
3,000     4.750%, 1/01/28 – FSA Insured    7/14 at 100.00    AAA    2,970,090 
6,215    Total New Mexico            6,150,818 
    New York – 4.5%             
2,700    Dormitory Authority of the State of New York, Revenue Bonds, Mount Sinai NYU Health Obligated    7/10 at 101.00    Ba1    2,889,729 
     Group, Series 2000A, 6.500%, 7/01/17             
2,000    New York City Municipal Water Finance Authority, New York, Water and Sewerage System Revenue    12/14 at 100.00    AAA    2,037,940 
     Bonds, Fiscal Series 2005B, 5.000%, 6/15/36 – FSA Insured             
3,000    New York State Tobacco Settlement Financing Corporation, Tobacco Settlement Asset-Backed and    6/11 at 100.00    AA–    3,168,180 
     State Contingency Contract-Backed Bonds, Series 2003B-1C, 5.500%, 6/01/16             
3,150    Triborough Bridge and Tunnel Authority, New York, Convention Center Bonds, Series 1990E,    No Opt. Call    AA–    3,350,214 
     7.250%, 1/01/10             
10,850    Total New York            11,446,063 
    North Carolina – 0.6%             
1,500    Charlotte-Mecklenburg Hospital Authority, North Carolina, Healthcare System Revenue Bonds,    1/11 at 101.00    AA    1,514,775 
     Carolinas Healthcare System, Series 2001A, 5.000%, 1/15/31             
    Oklahoma – 0.4%            
1,000    Norman Regional Hospital Authority, Oklahoma, Hospital Revenue Bonds, Series 2005,    9/16 at 100.00    BBB–    1,007,320 
     5.375%, 9/01/36             
    Pennsylvania – 2.6%             
1,020    Carlisle Area School District, Cumberland County, Pennsylvania, General Obligation Bonds,    9/09 at 100.00    Aaa    1,043,980 
     Series 2004A, 5.000%, 9/01/20 – FGIC Insured             
545    Dauphin County General Authority, Pennsylvania, Health System Revenue Bonds, Pinnacle Health    2/09 at 101.00    AAA    562,173 
     System Project, Series 1999, 5.125%, 8/15/17 – MBIA Insured             
455    Dauphin County General Authority, Pennsylvania, Health System Revenue Bonds, Pinnacle Health    2/09 at 101.00    AAA    472,868 
     System Project, Series 1999, 5.125%, 8/15/17 (Pre-refunded 2/15/09) – MBIA Insured             
1,000    Philadelphia Authority for Industrial Development, Pennsylvania, Airport Revenue Bonds,    7/11 at 101.00    AAA    1,054,880 
     Philadelphia Airport System Project, Series 2001A, 5.500%, 7/01/17 – FGIC Insured             
     (Alternative Minimum Tax)             
3,250    Philadelphia School District, Pennsylvania, General Obligation Bonds, Series 2002A, 5.500%,    2/12 at 100.00    AAA    3,497,163 
     2/01/31 (Pre-refunded 2/01/12) – FSA Insured             
6,270    Total Pennsylvania            6,631,064 
    Puerto Rico – 1.2%             
3,000    Puerto Rico Housing Finance Authority, Capital Fund Program Revenue Bonds, Series 2003,    12/13 at 100.00    AA    3,079,350 
     5.000%, 12/01/20             
    Rhode Island – 2.1%             
5,000    Rhode Island Tobacco Settlement Financing Corporation, Tobacco Settlement Asset-Backed Bonds,    6/12 at 100.00    BBB    5,242,250 
     Series 2002A, 6.250%, 6/01/42             
    South Carolina – 4.4%             
700    Dorchester County School District 2, South Carolina, Installment Purchase Revenue Bonds,    12/14 at 100.00    A    729,302 
     GROWTH, Series 2004, 5.250%, 12/01/20             
620    Florence, South Carolina, Water and Sewerage Revenue Bonds, Series 2000, 5.750%, 3/01/20 –    3/10 at 101.00    AAA    661,621 
     AMBAC Insured             
4,000    Greenville County School District, South Carolina, Installment Purchase Revenue Bonds, Series    12/12 at 101.00    AA– (3)    4,433,360 
     2002, 5.875%, 12/01/19 (Pre-refunded 12/01/12)             
2,500    Lexington County Health Service District, South Carolina, Hospital Revenue Refunding and    11/13 at 100.00    A    2,694,200 
     Improvement Bonds, Series 2003, 6.000%, 11/01/18             
2,435    Medical University Hospital Authority, South Carolina, FHA-Insured Mortgage Revenue Bonds,    8/14 at 100.00    AAA    2,550,419 
     Series 2004A, 5.250%, 2/15/21 – MBIA Insured             
10,255    Total South Carolina            11,068,902 
    South Dakota – 0.4%             
1,000    South Dakota Health and Educational Facilities Authority, Revenue Bonds, Sioux Valley    11/14 at 100.00    A+    1,019,400 
     Hospitals, Series 2004A, 5.250%, 11/01/34             
    Texas – 12.6%             
4,000    Brazos River Harbor Navigation District, Brazoria County, Texas, Environmental Facilities    5/12 at 101.00    A–    4,340,960 
     Revenue Bonds, Dow Chemical Company Project, Series 2002A-6, 6.250%, 5/15/33 (Mandatory             
     put 5/15/17) (Alternative Minimum Tax)             
1,500    Central Texas Regional Mobility Authority, Travis and Williamson Counties, Toll Road Revenue    1/15 at 100.00    AAA    1,501,545 
     Bonds, Series 2005, 5.000%, 1/01/45 – FGIC Insured             
1,270    Cleveland Housing Corporation, Texas, FHA-Insured Section 8 Assisted Mortgage Revenue    7/06 at 100.00    AAA    1,271,918 
     Refunding Bonds, Series 1992C, 7.375%, 7/01/24 – MBIA Insured             
1,000    Dallas Area Rapid Transit, Texas, Senior Lien Sales Tax Revenue Bonds, Series 2001, 5.000%,    12/11 at 100.00    AAA    1,010,590 
     12/01/31 – AMBAC Insured             
2,500    Harris County Health Facilities Development Corporation, Texas, Hospital Revenue Bonds, Texas    No Opt. Call    AAA    2,716,625 
     Children’s Hospital, Series 1995, 5.500%, 10/01/16 – MBIA Insured (ETM)             
3,000    Harris County Health Facilities Development Corporation, Texas, Thermal Utility Revenue Bonds,    11/13 at 100.00    AAA    3,035,790 
     TECO Project, Series 2003, 5.000%, 11/15/30 – MBIA Insured             
5,050    Harris County-Houston Sports Authority, Texas, Junior Lien Revenue Bonds, Series 2001H,    11/31 at 53.78    AAA    719,625 
     0.000%, 11/15/41 – MBIA Insured             
2,000    Houston, Texas, Subordinate Lien Airport System Revenue Bonds, Series 2002A, 5.625%, 7/01/20 –    7/12 at 100.00    AAA    2,116,680 
     FSA Insured (Alternative Minimum Tax)             
3,125    Katy Independent School District, Harris, Fort Bend and Waller Counties, Texas, General    2/12 at 100.00    AAA    3,154,563 
     Obligation Bonds, Series 2002A, 5.000%, 2/15/32             
1,400    Kerrville Health Facilities Development Corporation, Texas, Revenue Bonds, Sid Peterson    No Opt. Call    BBB–    1,403,976 
     Memorial Hospital Project, Series 2005, 5.375%, 8/15/35             
220    Killeen Independent School District, Bell County, Texas, General Obligation Bonds, Series    2/08 at 100.00    AAA    223,210 
     1998, 5.000%, 2/15/14             
780    Killeen Independent School District, Bell County, Texas, General Obligation Bonds, Series    2/08 at 100.00    AAA    794,703 
     1998, 5.000%, 2/15/14 (Pre-refunded 2/15/08)             
1,000    Lewisville Independent School District, Denton County, Texas, General Obligation Bonds, Series    8/11 at 100.00    AAA    1,021,690 
     2004, 5.000%, 8/15/23             
4,750    Sam Rayburn Municipal Power Agency, Texas, Power Supply System Revenue Refunding Bonds, Series    10/12 at 100.00    AA    4,995,480 
     2002A, 5.500%, 10/01/17 – RAAI Insured             
1,250    Texas Water Development Board, Senior Lien State Revolving Fund Revenue Bonds, Series 1996B,    1/07 at 100.00    AAA    1,256,738 
     5.125%, 7/15/18             
500    Texas Water Development Board, Senior Lien State Revolving Fund Revenue Bonds, Series 2000A,    7/10 at 100.00    AAA    528,870 
     5.625%, 7/15/13             
1,560    Texas, General Obligation Bonds, Water Financial Assistance Program, Series 2003A, 5.125%,    8/13 at 100.00    Aa1    1,561,669 
     8/01/42 (Alternative Minimum Tax)             
34,905    Total Texas            31,654,632 
    Utah – 0.6%             
1,435    Salt Lake City and Sandy Metropolitan Water District, Utah, Water Revenue Bonds, Series 2004,    7/14 at 100.00    Aaa    1,479,370 
     5.000%, 7/01/21 – AMBAC Insured             
    Vermont – 2.7%             
3,000    Vermont Housing Finance Agency, Multifamily Housing Bonds, Series 1999C, 5.800%, 8/15/16 –    2/09 at 100.00    AAA    3,076,620 
     FSA Insured             
3,600    Vermont Industrial Development Authority, Revenue Refunding Bonds, Stanley Works Inc., Series    9/06 at 100.00    A    3,607,056 
     1992, 6.750%, 9/01/10             
6,600    Total Vermont            6,683,676 
    Virginia – 0.5%             
250    Norfolk, Virginia, Water Revenue Bonds, Series 1995, 5.750%, 11/01/13 – MBIA Insured    11/07 at 100.00    AAA    255,345 
1,000    Virginia Transportation Board, Transportation Revenue Refunding Bonds, U.S. Route 58 Corridor    5/07 at 101.00    AA+    1,018,190 
     Development Program, Series 1997C, 5.125%, 5/15/19             
1,250    Total Virginia            1,273,535 
    Washington – 3.6%             
2,000    Washington State Healthcare Facilities Authority, Revenue Bonds, Catholic Health Initiatives,    12/07 at 101.00    AAA    2,043,880 
     Series 1997A, 5.125%, 12/01/17 – MBIA Insured             
6,715    Washington State Healthcare Facilities Authority, Revenue Bonds, Sisters of Providence Health    10/11 at 100.00    AAA    6,918,397 
     System, Series 2001A, 5.125%, 10/01/17 – MBIA Insured             
8,715    Total Washington            8,962,277 
    Wisconsin – 2.0%             
1,000    Wisconsin Health and Educational Facilities Authority, Revenue Bonds, Wheaton Franciscan    8/13 at 100.00    A    1,047,840 
     Services Inc., Series 2003A, 5.500%, 8/15/18             
4,000    Wisconsin Housing and Economic Development Authority, Home Ownership Revenue Bonds, Series    3/12 at 100.00    AA    4,061,520 
     2002G, 4.850%, 9/01/17             
5,000    Total Wisconsin            5,109,360 
$      253,160    Total Long-Term Investments (cost $239,456,008) – 98.1%            246,933,701 
    Short-Term Investments – 0.4%             
985    Idaho Health Facilities Authority, Revenue Bonds, St. Luke’s Regional Medical Center, Variable      A-1+    985,000 
     Rate Demand Obligations, Series 2005, 3.980%, 7/01/35 – FSA Insured (4)             
985    Total Short-Term Investments (cost $985,000)            985,000 
$      254,145    Total Investments (cost $240,441,008) – 98.5%            247,918,701 
    Other Assets Less Liabilities – 1.5%            3,691,383 
    Net Assets – 100%           $   251,610,084 

(1)    Optional Call Provisions: Dates (month and year) and prices of the earliest optional call or 
    redemption. There may be other call provisions at varying prices at later dates. Certain 
    mortgage-backed securities may be subject to periodic principal paydowns. 
(2)    Ratings: Using the higher of Standard & Poor's or Moody's rating. Ratings below BBB by Standard 
    & Poor's Group or Baa by Moody's Investor Service, Inc. are considered to be below investment grade. 
(3)    Backed by an escrow or trust containing sufficient U.S. Government or U.S. Government agency 
    securities which ensure the timely payment of principal and interest. Such investments are 
    normally considered to be equivalent to AAA rated securities. 
(4)    Investment has a maturity of more than one year, but has variable rate and demand features which 
    qualify it as a short-term investment. The rate disclosed is that in effect at the end of the reporting 
    period. This rate changes periodically based on market conditions or a specified market index. 
(ETM)    Escrowed to maturity. 

Income Tax Information

The following information is presented on an income tax basis. Differences between amounts for financial statement and federal income tax purposes are primarily due to the treatment of paydown gains and losses, timing differences in recognizing taxable market discount and timing differences in recognizing certain gains and losses on investment transactions.

At June 30, 2006, the cost of investments was $240,340,756.

Gross unrealized appreciation and gross unrealized depreciation of investments at June 30, 2006, were as follows:

Gross unrealized:     
  Appreciation    $8,403,210 
  Depreciation    (825,265) 
Net unrealized appreciation (depreciation) of investments    $7,577,945 

Item 2. Controls and Procedures.

  1. The registrant's principal executive and principal financial officers, or persons performing similar functions, have concluded that the registrant's disclosure controls and procedures (as defined in Rule 30a-3(c) under the Investment Company Act of 1940, as amended (the "1940 Act") (17 CFR 270.30a-3(c))) are effective, as of a date within 90 days of the filing date of this report that includes the disclosure required by this paragraph, based on their evaluation of the controls and procedures required by Rule 30a-3(b) under the 1940 Act (17 CFR 270.30a-3(b)) and Rule 13a-15(b) or 15d-15(b) under the Securities Exchange Act of 1934 (17 CFR 240.13a-15(b) or 240.15d-15(b)).
  2. There were no changes in the registrant's internal control over financial reporting (as defined in Rule 30a-3(d) under the 1940 Act (17 CFR 270.30a-3(d)) that occurred during the registrant's last fiscal quarter that have materially affected, or are reasonably likely to materially affect, the registrant's internal control over financial reporting.

Item 3. Exhibits.

File as exhibits as part of this Form a separate certification for each principal executive officer and principal financial officer of the registrant as required by Rule 30a-2(a) under the 1940 Act (17 CFR 270.30a-2(a)), exactly as set forth below: EX-99 CERT Attached hereto.


SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

(Registrant)         Nuveen Select Tax-Free Income Portfolio 2        

By (Signature and Title)*          /s/ Jessica R. Droeger                     
                                                    Jessica R. Droeger
                                                    Vice President and Secretary

Date         August 28, 2006        

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment Company Act of 1940, this report has been signed below by the following persons on behalf of the registrant and in the capacities and on the dates indicated.

By (Signature and Title)*         /s/ Gifford R. Zimmerman                    
                                                   Gifford R. Zimmerman
                                                   Chief Administrative Officer (principal executive officer) 

Date         August 28, 2006        

By (Signature and Title)*         /s/ Stephen D. Foy                              
                                                   Stephen D. Foy
                                                   Vice President and Controller (principal financial officer) 

Date        August 28, 2006        

* Print the name and title of each signing officer under his or her signature.