【Abstract】 Objective To investigate and analyze the expression of Gab1 and programmed death ligand1 (PDL1) in epithelial ovarian cancer tissues, and explore the correlation between Gab1, PDL1 protein and clinicopathological characteristics and prognosis in patients with epithelial ovarian cancer. Methods 86 epithelial ovarian cancer patients in our hospital from May 2008 to May 2014 were used as the objects in the study. The clinical value and followup data of all patients were analyzed by a retrospective analysis. Collecting 85 cancer tissues (observation group) and 86 adjacent normal tissues (the control group) from 86 epithelial ovarian cancer patients and used as the research objects according to the data. The protein level of Gab1 and PDL1 protein in all tissues were measured, and recording the patients age, body mass index and other clinical data and tumor, Gab1 and PDL1 protein levels and prognosis according to the data and test results. Results The expression levels of Gab1 and PDL1 in the epithelial ovarian carcinoma tissues of epithelial ovarian cancer patients were significantly higher than those in adjacent normal tissues (P＜0.05). The positive expression of PDL1 Gab1 were increased significantly following with higher clinical stage lower the degree of differentiation and lymph node metastasis of epithelial ovarian cancer patients (P＜0.05). The 3 year survival rates of patients with Gab1 positive and negative expressions were 7273% and 4286%, while the 3 year survival rates of patients with PDL1 positive and negative expressions were 7368% and 4583% (P＜0.05). The results of single factor non conditional Cox regression model shows that there were differences in epithelial ovarian cancer patients with different clinical stages, differentiation, or lymph node metastasis and Gab1 and PDL1 expression between the prognosis of survival time (P＜0.05). The results of multivariate Co X proportional hazards regression analysis indicated that clinical stage III, IV, poorly differentiated, lymph node metastasis and positive expressions of Gab1 and PDL1 were independent risk factors for the prognosis of epithelial ovarian cancer patients (P＜0.05). Conclusion The expressions of Gab1 and PDL1 protein was increased in epithelial ovarian cancer, and increased with the aggravation. The positive expression of Gab1 and PDL1 combine with clinical stage III ~ IV, low differentiation and lymph node metastasis were independent prognostic risk factors in epithelial ovarian cancer patients. It can be used as the clinical evaluation index of progression and prognosis of epithelial ovarian cancer patients.