Hyperandrogenism is a common finding in premenopausal age and is generally caused by polycystic ovarian syndrome or other benign disease. Androgen-secreting tumors represent only 0.2 % of the causes of hyperandrogenism and usually present with severe clinical features, abrupt onset, and very high androgens levels. We describe here three cases of occult ovarian Leydig cell tumors suspected on the basis of severe clinical features of hyperandrogenism rapidly worsening, with elevated serum total testosterone levels, in which bilateral ovariectomy was performed and tumor was confirmed by post-operative histology. In all three cases, imaging was negative for ovarian tumor. Moreover, in one case the confounding concomitant finding of bilateral adrenal masses posed an additional challenge. Our experience highlights that testosterone levels represent the most helpful marker in the diagnosis of androgen-secreting ovarian tumor. In the absence of imaging findings, bilateral ovariectomy should be indicated, if supported by unequivocal clinical and laboratory data.