Granulosa cell tumors, arised from granulosa cells, are the most common sex-cord gonadostromal tumor of the ovary. In the present report, granulosa cell tumor in two dogs was described with its clinical and pathologic findings. In the first case (2-years-old, mongrel bitch), moderate vulvar edema and hemorrhagic vaginal discharge was observed in clinical examination. In transabdominal ultrasonography, two cysts, 8.0 and 10.0 mm in diameters, were determined on the right ovary. In the second case (9-years-old, German shepherd spayed bitch), severe vulvar edema and hemorrhagic vaginal discharge for three months were reported. A cystic formation surrounded by a hyperechogenic tissue was detected in the right paralumbal area during transabdominal ultrasonography. Macroscopically, in the first case surfaces of the both ovary had, many grayish-white nodules with firm in concistency with sizes varying from 1.0 mm to 3.0 mm in diamaters. In addition, the surface of the right ovary had also two serous cysts with 8.0 mm and 10.0 mm in diamaters. Microscopically, in both cases, cystic or solid neoplastic areas surrounded by fibrous tissue were observed. The neoplastic areas were consisted of one or more rows of pleomorphic granulosa cells with oval or round nuclei and vacuolated cytoplasm. In some of the these neoplastic structures, centrally located globular eosinophlic Call-Exner body were noted. Following postoperative treatment, a decrease in vulvar edema and vaginal bleeding were observed, and full recovery was obtained in both cases in the next weeks.