Objective:To investigate the pro-apoptosis effects of triptolide in human with endometrial cancer cell line (HEC-1B) on proliferation and apoptosis and its underlying mechanisms. Methods:①The Cell Counting Kit-8 (CCK-8)was performed to measure the inhibitive effect of triptolide on the apoptosis on cell proliferation.②The apoptosis and the change of caspase-3/9 in HEC-1B by pretreatment with the z-VAD-fmk(pan-capase inhibitor)were detected by CCK-8 and Western blot. Western blot was used to examine the expression of caspase-3/9,bcl-2. Results:The proliferation of HEC-1B was significantly decreased by triptolide in a dose-and time-dependent manner(P < 0.01),and the effect in 48 h/72 h was obvious. The pan-caspase inhibitor z-VAD-fmk pretreatment reduced triptolide-induced apoptosis in HEC-1B, but the result was still higher than the control group (P < 0.01). Triptolide increased the levels of caspase-3/9 expression while reduced bcl-2 expression in the dose-dependent manner(P < 0.05). Conclusion:Triptolide functions as an effective apoptotic inducer in a caspase-dependent apoptosis via mitochondrial mechanism in human endometrial cancer (HEC-1B).