CERTIFICATIONS PURSUANT TO SECTION 906
EX-99.906CERT

                                  CERTIFICATION

R. Jay Gerken, Chief Executive Officer, and Richard L. Peteka, Chief Financial
Officer of High Income Opportunity Fund Inc. (the "Registrant"), each certify to
the best of his or her knowledge that:

1. The Registrant's periodic report on Form N-CSR for the period ended September
30, 2003 (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
High Income Opportunity Fund Inc.          High Income Opportunity Fund Inc.



/s/ R. Jay Gerken                          /s/ Richard L. Peteka
- ------------------------------------       -------------------------------------
R. Jay Gerken                              Richard L. Peteka
Date: December 15, 2003                    Date: December 15, 2003

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.