Abstract: Objective To investigate the sensitiziation of xiaoaiping injection to oxaliplatin in inhibitory of human ovarian cancer Caov-3 cells proliferation and explore the mechanism. Methods Caov-3 cells were treated with oxaliplatin combined with or without xiaoaiping,and the control group was treated with PBS.The inhibitory effects on cell proliferation were examined by MTT assay and oxaliplatin's IC50 was generated.The apoptosis morphological changes in Caov-3 cells were observed by fluorescent microscopy.Apoptosis peak was analyzed with FACScan flow cytometry.The expression of caspase-3 in Caov-3 cells was analyzed by Western blot. Results In Caov-3 cells,the value of IC50 of OXA combined with xiaoaiping were significantly lower than that of OXA alone.And cell survival rate of the group of OXA combined with xiaoaiping was lower than that of group treated by OXA alone,too.Besides,xiaoaiping increased OXA induced apoptosis in morphological and DNA contents' changes.In addition,the cleavage of caspase-3,a hallmark of apoptosis protein was increased in Caov-3 cells treated with oxaliplatin combined with xiaoaiping. Conclusion Xiaoaiping can sensitize the OXA in inhibition of human ovarian cancer Caov-3 cells proliferation.Activation of caspase-3 might be involved in the mechanisms of the sensitization.