CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350,
                             AS ADOPTED PURSUANT TO
                  SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002


Name of Issuer: VANGUARD EXPLORER FUND

     In connection with the Report on Form N-CSR of the above-named  issuer that
is accompanied by this certification,  the undersigned hereby certifies,  to his
knowledge, that:

1.   The Report fully complies with the  requirements of Section 13(a) or 15 (d)
     of the Securities Exchange Act of 1934; and

2.   The information  contained in the Report fairly presents,  in all materials
     respects, the financial condition and results of operations of the issuer.


Date:  June 16, 2003                                 /s/ John J. Brennan
                                                        -------------------
                                                         John J. Brennan
                                                         Chief Executive Officer









                CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350,
                             AS ADOPTED PURSUANT TO
                  SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002


Name of Issuer:  VANGUARD EXPLORER FUND

     In connection  with the Report on Form N-CSR of the  above-named  issuer is
accompanied by this  certification,  the undersigned  hereby  certifies,  to his
knowledge, that:

1.   The Report fully complies with the  requirements of Section 13(a) or 15 (d)
     of the Securities Exchange Act of 1934; and

2.   The information  contained in the Report fairly presents,  in all materials
     respects, the financial condition and results of operations of the issuer.


Date:  June 16, 2003                                     /s/ Thomas J. Higgins
                                                            -------------------
                                                             Thomas J. Higgins
                                                             Treasurer