Background: As natural medicines in Asia, curcumin and triptolide extracted from different drug plants have proven to possess anticancer potential and widely used for anti-cancer research. The present study attempted to clarify that curcumin and triptolide synergistically suppress ovarian cancer cell growth in vitro. Methods: To test synergic effects, cell viability and apoptosis were analyzed after curcumin and triptolide combination treatment on ovarian cancer cell lines. Synergistic effects on apoptosis induction were determined by lactate dehydrogenase (LDH) leakage assay, intracellular reactive oxygen species (ROS) assay, mitochondrial membrane potential (MMP) loss assay and flow cytometry analysis. Critical regulators of cell proliferation and apoptosis related were analyzed by qRT-PCR and Western blotting. Results: We showed that the combination of curcumin and triptolide could synergistically inhibit ovarian cancer cell growth, and induce apoptosis, which is accompanied by HSP27 and HSP70, indicating that HSP27 and HSP70 play the important role in the synergic effect. Conclusions: From the result present here, curcumin and triptolide combination with lower concentration have a synergistic anti-tumor effect on ovarian cancer and which will have a good potential in clinical applications.