PURPOSE: To determine, through an analysis of radiologic findings, whether the findings of granulosa cell tumors (GCTs) of the ovary are specific. MATERIALS AND METHODS: The radiologic findings (ultrasonography, computed tomography, and magnetic resonance imaging) of 16 pathologically proven ovarian GCTs in 15 patients were retrospectively analysed for the site of origin, staging, largest diameter, margin, solid and/or cystic components, degree of enhancement, and associated endometrial hyperplasia, ascites, and local and/or distant metastasis. RESULTS: Unilateral ovarian GCTs were found in 14 patients, and bilateral tumors in one. Of a totalof 16 tumors, 13 were of the adult type, and three were juvenile; their largest diameter ranged from 1 to 26 (mean, 15.6)cm. Eleven tumors were well-defined, two were cystic, and one small tumor was solid. Of 13 mixed tumors, three had hemorrhagic portions, and five had multilocular cystic portions. Metastases to the uterus, tubes, rectum, lymph nodes, or liver were found in six patients, and associated endometrial hyperplasia in two. CONCLUSION: Radiologically, ovarian GCTs showed well-defined or encapsulated soft tissue masses with some hemorrhagic, multiocular or focal cystic components, as well as associated endometrial thickening and local or distant metastasis. These and clinical findings may be useful in the diagnosis of ovarian GCTs.