Tumor angiogenesis has a role in tumor invasion and metastasis in various types of tumors. In this study, ovarian epithelial tumor tissues from 41 cases of serous tumors and 50 cases of mucinous tumors were analyzed for the expression of VEGF by immunohistochemical stain. And, we quantified microvessel counts (MC) using monoclonal antibody for CD31. The serous tumors included 19 cases of benign, 3 cases of borderline and 19 cases of malignant tumors. The mucinous tumors included 20 cases of benign, 16 cases of borderline and 8 cases of malignant tumors. As results, the MC and VEGF expression in carcinomas were significantly higher than in benign or borderline malignancy of both serous and mucinous tumors. And, relationship between MC and VEGF expression was present. But, there was no significant correlation according to FIGO stage, tumor size or patient's age. These results suggest that other angiogenic factors may affect in the regulation of angiogenesis. In conclusion, MC and VEGF expression is useful indicator of progression in ovarian serous and mucinous tumors. But, the prognostic significance cannot be fully established and additionally long-term follow up study for patient's survival rate is needed.