Schwannomas of the sacral plexus are retroperitoneal tumors, usually benign, that result from proliferation of perineural cells. They are rare, pelvic, well defined tumors that present infrequently as gynecologic masses. Misdiagnosis is not uncommon in these cases, since these masses are not often encountered in clinical practice and preoperative imaging methods can be only suggestive of the diagnosis. Furthermore, these masses are not often encountered in clinical practice. We report a case of a 28-year-old woman who presented with a pelvic mass and obscure clinical signs. Imaging methods suggested that this tumor was most probably an ovarian mass of embryonic origin. After dissection by laparotomy, the microscopic examination showed typical futures of a neurile­moma (ancient schwannoma). The goal of the operating intervention is to excise the tumor avoiding major trauma, thus coopera­tion between surgeons is indispensable. The patient has had no motor or sensory disturbances after surgery.