The purpose of this study was to characterize patients diagnosed with synchronous primary carcinomas of the endometrium and ovary. Between 1985 and 2002, 46 patients with synchronous primary carcinomas of the endometrium and ovary were identified. Clinical and pathological information was obtained from the database and pathological reports. Kaplan-Meier survival analysis, log rank tests of survival differences, and multivariate Cox regression analysis were performed. Median age at diagnosis was 55 years. Twenty-one patients (46%) had an endometrioid histology both of their endometrial and ovarian cancers. Patients with younger age, high uterine differentiation grade, and early-stage ovarian cancer had a more favorable prognosis than those with older age, low grade of differentiation, and advanced stage disease. The Cox proportional hazards model analysis indicates that young age and high grade of differentiation are independent prognostic factors. In this series of patients, women with synchronous primary cancer of the endometrium and ovary were young; the survival rate was greater in patients aged less than 50 years and in patients with an early stage. No significantly different survival between patients with endometrioid carcinoma and patients with non-endometrioid carcinomas was detected.