Abstract: We examined the cytotoxic activities of recombinant human tumor necrosis factor（rHTNF）alone and in combination with recombinant human interferon-γ,（rHIFN-γ）,against twohuman ovarian cancer cell lines,OVCAR3 and CAOV3,using the MTT assay. The results sho-wed that cytotoxicities of the two cytokines against the two cell lines were dose-dependent,andsynergistic enhancement cytotoxicities of rHIFN-γin combination with a low dose of rHTNF onthe two cell lines were remarkable.This study suggest that the combination therapy of rHTNFand rHIFN-γ will be a new approach against human ovarian cancer in clinic practice.