〔Abstract〕 Objective To investigate the effect of cancer-associated fibroblasts(CAFs) on the cisplatin resistance of ovarian cancer cells,and to explore the possible mechanisms. Methods CAFs and NFs were isolated and cultured respectively from 10 cases of epithelial ovarian cancer tissue and 10 cases of normal ovarian epithelial tissue.The isolated CAFs were identified by immunofluorescence assay.Indirect co-culture system was established by collecting CAFs or NFs culture supernatants and ovarian cancer SKOV3 cells.Cell proliferation,cisplatin toxicity and cell migration ability were investigated by CCK8 and scratch assay.The content of reactive oxygen species(ROS) in the co-culture system was assessed by DCFH-DA method.The expression of SKOV3 cell resistance-related genes YAP,CTGF and Cyr61 at mRNA and protein levels were detected by real-time quantitative PCR(qPCR) and Western blot. Results Primary ovarian cancer CAFs were successfully separated.The expressions of α-SMA and FAP protein in the separated CAFs were significantly higher than those in the NFs.Co-cultured with CAFs,the proliferation,the half inhibitory concentration(IC50)of cisplatin and migration abilities of SKOV3 cells significantly enhanced.Co-cultured with CAFs,ROS content of SKOV3 cells increased.Co-cultured with CAFs,the expressions of YAP,CTGF and Cyr61 of SKOV3 cells enhanced at mRNA and protein levels. Conclusion CAFs can promote the proliferation and migration of ovarian cancer cells and reduce the sensitivity of ovarian cancer SKOV3 cells to cisplatin.The mechanism is related to ROS promoting autophagy in ovarian cancer cells on the one hand,and it is related to up-regulation of drug resistance genes YAP,CTGF and Cyr61 in ovarian cancer cells on the other hand.