A clinicopathologic study of 30 patients with mixed mesodermal tumor of the endometrium is presented. An over‐all 5‐year survival rate of 21% was obtained which compares favorably with figures in the literature. Prompt hysterectomy and bilateral salpingo‐oopherectomy is the treatment of choice. Preoperative irradiation destroys the local tumor in a minority of cases, does not improve the survival rate and delays definitive surgery for a tumor known to grow and spread rapidly. Histologic subclassification does not correlate well with survival but superficial growth and lack of penetration of the myometrium are significant prognostic factors.