Sertoli-Leydig cell tumor belongs to the group of sex cord-stromal tumors of the ovary. These neoplasms account for less than 0.5% of all ovarian tumors and are more often encountered in young women between the ages of 20 and 30 years who usually become virilized. We described an unusual case of Sertoli-Leydig cell tumor in a postmenopausal women who presented with a solid right pelvic mass, a large amount of ascites, and laboratory tests revealing an elevated CA125, all suggesting a pelvic malignancy. Although five similar cases of postmenopausal women with Sertoli-Leydig cell tumor of ovary have been reported in the literature, we believe that this is an useful addition to the literature.