MicroRNAs (miRs) have been reported to be associated with the development of numerous types of cancer. However, the function of miRs in human ovarian carcinoma chemoresistance remains largely undefined. In the present study, cell chemotherapy combined with a Cell Counting Kit-8 assay demonstrated that miR-20a performed important roles in ovarian cancer cells chemoresistance. Flow cytometry, cellular proliferation assays and Transwell assays results revealed that the proliferation and migration rates of OVCAR3/DDP cells were increased in comparison with parental cells. Western blot analysis results suggested that epithelial-mesenchymal transition (EMT) activated by miR-20a contributed to OVCAR3/DDP cell migration. The present study highlighted the importance of miR-20a in regulating the chemoresistant properties of OVCAR3 cells and promoting cisplatin-resistant cell migration by activating EMT. The results of present study may therefore provide novel insights into reversing the chemoresistance of ovarian cancer and improving its treatment.