Adult granulosa cell tumors of the ovary are rare neoplasms, accounting for less than 5% of all ovarian malignancies. In addition to the tumor stage, residual disease, patient age, tumor size, extent of surgery, and also some histologic factors have been reported to be of prognostic importance. Tumor registries were screened for all patients treated between 1979 and 1998 for ovarian tumors at the University of Istanbul. There were 952 ovarian carcinomas, of which 47 were granulosa cell tumors. All charts were reviewed, and the clinical data were extracted. Prognostic factors and treatment results were evaluated retrospectively. The median follow-up was 84 (range: 6-141 months) months. According to univariate analysis, there were only two significant factors for overall survival (OS): stage and presence of residual disease. The OS of the 23 patients with early stage (mean, 122 months; median, unreached) was significantly (p = 0.0001) better than the OS of the 22 patients with advanced stage (mean, 34 months; median, 21 months). A significant difference (p = 0.0004) in OS was also observed between patients with residual (mean, 42 months; median, 21 months) and nonresidual (mean, 108 months; median, unreached) disease. In a multivariate analysis, only stage remained statistically significant (p = 0.0001). The overall 5-year survival rate was 55% and median survival after recurrence was 21 months. Despite the small number of patients, the study showed that stage and macroscopic residual disease are significant prognostic factors. The benefit of chemotherapy and radiotherapy remains controversial.