Purpose: To study the killing effects on osteosarcoma cells of cinobufacini and cisplatin in combination and the related mechanisms so as to explore the chemotherapeutic method with integrated traditional Chinese and Western medicines. Methods: Cinobufacini and cisplatin were applied to OS732 cells singly or jointly and survival rates were measured by MTT assay. Changes in cellular shape were observed with inverted phase contrast and fluorescence microscopy and apoptosis rates were analyzed with flow cytometry (FCM). Immunocytochemistry were used to examine the Fas expression of OS732 cells. Results: The combination of cinobufacini and cisplatin had the effect of up-regulating Fas expression and inducing apoptosis. The survival rate of combined application of 100 ${mu}g/ml$ cinobufacini and 1 ${mu}g/ml$ cisplatin on OS-732 cells was significantly lower than with either of the agents alone (p<0.01). Changes in cellular shape and apoptotic rates also indicated the apoptosis-inducing effects of combined application were much enhanced. Conclusion: The combination of cinobufacini and cisplatin demonstrated strong killing effects on OS-732 cells which might be related to up-regulation of Fas expression.