CERTIFICATIONS PURSUANT TO SECTION 906
EX-99.906CERT

                                  CERTIFICATION

R. Jay Gerken, Chief Executive Officer, and Richard L. Peteka, Chief Financial
Officer of Smith Barney Muni Funds - Massachusetts Money Market Portfolio (the
"Registrant"), each certify to the best of his knowledge that:

      1. The Registrant's periodic report on Form N-CSR for the period ended
March 31, 2004 (the "Form N-CSR") fully complies with the requirements of
section 15(d) of the Securities Exchange Act of 1934, as amended; and

      2. The information contained in the Form N-CSR fairly presents, in all
material respects, the financial condition and results of operations of the
Registrant.


Chief Executive Officer                     Chief Financial Officer
Smith Barney Muni Funds -                   Smith Barney Muni Funds -
Massachusetts Money Market Portfolio        Massachusetts Money Market Portfolio



/s/ R. Jay Gerken                           /s/ Richard L. Peteka
-------------------------------             ------------------------------------
R. Jay Gerken                               Richard L. Peteka
Date: June 4, 2004                          Date: June 4, 2004

This certification is being furnished to the Securities and Exchange Commission
solely pursuant to 18 U.S.C. ss. 1350 and is not being filed as part of the Form
N-CSR with the Commission.