en Gynecology & Obstetrics Gynecology & Obstetrics case report case report <font size="3" face="Times New Roman"> </font><font size="3"><font face="Calibri">Leydig stromal cell tumor is a rare ovarian tumor that belongs to the group of sex-cord stromal tumors. They produce testosterone leading to hyperandrogenism. We present a 41yr old woman with symptoms of virilization and a mass of right adenex via ultra Sonography, and a rise of total and free serum testosterone. An ovarian source of androgen was suspected and a surgery performed. A diagnosis of leydig-stromal cell tumor was confirmed. Our report is a reminder that although idiopathic hirsutism and other benign androgen excess disorder like Polycystic Ovarian Syndrome (PCOs) are common, ovarian mass should be considered in differential diagnosis.<p></p></font></font><font size="3" face="Times New Roman"> </font> Leydig stromal cell tumor, Androgen secreting neoplasm , Virilizing ovarian tumors, Sex cordstromal cell tumor. 185 188 http://mjiri.iums.ac.ir/browse.php?a_code=A-10-1-557&slc_lang=en&sid=1 Soheila Aminimoghaddam dr.aminimoghaddam@yahoo.com 20031947532846007431 20031947532846007431 No Department of gynecology, Firoozgar Hospital, Tehran University of Medical Sciences, Tehran, Iran. Atefeh-Sadat Ebrahimi md.a_ebrahimi@yahoo.com.sg 20031947532846007432 20031947532846007432 Yes Department of gynecology, Firoozgar Hospital, Tehran University of Medical Sciences, Tehran, Iran. Forough Hashemi fhashemi54@yahoo.com 20031947532846007433 20031947532846007433 No Department of pathology, Firoozgar Hospital, Tehran University of Medical Sciences, Tehran, Iran.