MicroRNA-203 (miR-203), possessing tumor suppressive or promotive activities, has been found to be downregulated or upregulated in different cancer types. The purpose of this study was to investigate whether the increased expression of miR-203 can be used as a noninvasive diagnostic and prognostic biomarker in epithelial ovarian cancer (EOC). Real-time quantitative PCR was performed to detect the expression levels of miR-203 in EOC tissues. The expression levels of miR-203 were significantly higher in EOC tissues compared to adjacent non-cancerous tissues (p < 0.001). High expression of miR-203 was observed in 65.38 % (102/156) of EOC. In addition, high miR-203 expression was found to be closely correlated with advanced FIGO stage (p < 0.001), higher histological grade (p = 0.02), lymph node involvement (p < 0.001), and positive recurrence (p < 0.001). Moreover, high miR-203 expression was correlated with shorter overall survival (p < 0.001) and shorter progression-free survival (p < 0.001) of EOC patients. Furthermore, multivariate analysis showed that the status of miR-203 expression was an independent predictor for both overall survival and progression-free survival in EOC. These findings provide the convincing evidence for the first time that the upregulation of miR-203 may serve as a novel molecular marker to predict the aggressive tumor progression and unfavorable prognosis of EOC patients.