Ovarian Sertoli-Leydig cell tumors (SLCTs) are uncommon sex cord-stromal tumors. Moreover, SLCTs with heterologous mesenchymal elements are extremely rare and usually associated with poor differentiation and prognosis. Herein, the authors describe a case of SLCT involving the right ovary in a 16-year-old girl who presented with acute lower abdominal pain and fever. Serum investigation demonstrated abnormally elevated level of alpha-fetoprotein (AFP), slightly elevation of testosterone, and CA125 concentration. Right salpingo-oopherectomy was performed due to ovarian tumor torsion and then histopathological analysis revealed a poorly differentiated Sertoli-Leydig cell tumor with heterologous rhabdomyosarcomatous elements. A brief review of the literature was conducted to explore the management options for patients with SLCTs and the prognosis.