Objective To explore the effects of Sijunzi Decoction containing serum on the proliferation, migration, invasion, and epithelial mesenchymal transition of ovarian cancer cells, and the mechanism involved. Methods Human ovarian cancer cells (SKOV3) and human ovarian epithelial cells were cultured in vitro and randomly divided into blank control, sunitinib, and Sijunzi Decoction I, II, and III groups. The methyl thiazolyl tetrazolium assay was used to detect the proliferation of SKOV3 cells and human ovarian epithelial cells. The migration and invasion abilities of SKOV3 cells were examined using the scratch test and transwell test. The protein expressions of E-cadherin, N-cadherin, vimentin, RAS homolog gene family member A (RhoA), Ras-related C3 botulinum toxin substrate 1 (Rac1), and cell division cycle 42 (Cdc42) in SKOV3 cells were detected by western blotting. In addition, the mRNA expressions of RhoA, Rac1, and Cdc42 in SKOV3 cells were detected by real-time quantitative PCR ( qRT-PCR). Results There was no significant difference in the survival rate of human ovarian epithelial cells among the groups (P> 0. 05). Compared with the blank control group, the survival rate, wound healing rate, invasion number, protein expressions of N-cadherin and vimentin, and mRNA and protein expressions of RhoA, Rac1, and Cdc42 in SKOV3 cells in the sunitinib group were significantly lower (P<0. 05), and the protein expression of E-cadherin was significantly higher (P<0. 05). The survival rate, wound healing rate, invasion number, protein expressions of N-cadherin and vimentin, and mRNA and protein expressions of RhoA, Rac1, and Cdc42 in SKOV3 cells in the Sijunzi Decoction I, II, and III groups were decreased (P<0. 05), and the protein expression of E-cadherin was increased (P< 0. 05) dose-dependently. There was no significant difference in these indexes between the Sijunzi Decoction III and sunitinib groups ( P> 0. 05 ). Conclusions Sijunzi Decoction containing serum inhibits the proliferation, migration, invasion, and epithelial mesenchymal transition of human ovarian cancer cells, which may be related to inhibition of the RhoA/ Rac1 / Cdc42 signaling pathway activation.