Objective：To evaluate the expression of microRNA-145（miR-145）in epithelial ovarian cancer tissue and serum，and investigate the diagnosis and prognosis value of miR-145 as a biomarker for epithelial ovarian cancer. Methods：The expression of miR-145 in serum from 45 cases of epithelial ovarian cancer and 45 cases of healthy control，as well as in ovarian tissues from 45 cases of epithelial ovarian cancer and 8 cases of healthy control，was detected by real-time PCR. Results：The expressions of miR-145 in the serum and ovarian tissues of patients with epithelial ovarian cancer were significantly lower than those in healthy control（P＜0.01）. The expression of miR-145 decreased with the progression of the clinical stages（P＜0.05），but it is not correlated with age，histological classification，lymph node metastasis，histological grading and the increasing of CA125（P＞0.05）. ROC curves revealed that serum miR-145 might be a promising diagnostic biomarker for patients with epithelial ovarian cancer. Conclusion：MiR-145 act as a tumor suppressor in the development of epithelial ovarian cancer. MiR-145 may serve as a biomarker for diagnosis and predictor of epithelial ovarian cancer.