Dicer is an essential enzyme that processes micro (mi)-RNA precursors into mature miRNAs, and serves a critical role in cancer development and progression by regulating gene expression. However, the role of Dicer in cisplatin-mediated apoptosis and chemotherapy resistance in epithelial ovarian cancer (EOC) cells is poorly understood. In the present study, Dicer was expressed at low levels in cisplatin-resistant A2780 cells when compared with parental cells. In addition, knocking down Dicer using short hairpin RNA decreased the sensitivity of A2780 and CAOV3 cells to cisplatin. Furthermore, d ownregulating Dicer significantly inhibited cisplatin-induced apoptosis in ovarian cancer cells, and decreased the levels of proteins involved in apoptosis signaling pathways, including P73, P63, P53, caspase-9 and caspase-3. These findings indicated that Dicer may be a promising target for overcoming drug resistance in ovarian cancer.