Leiomyomas are common benign gynecologic tumors occurring in up to 30% of women. Round ligament leiomyomas however are very rare and, if symptomatic, can present as an inguinal hernia. We report the case of a 47-year-old woman who presented with an irreducible inguinal mass consistent with an incarcerated hernia. Intraoperatively, the mass was found to be a round ligament leiomyoma, a diagnosis that was confirmed by histopathology following excision of the mass. Although rare, round ligament leiomyomas should be part of the differential diagnosis of an inguinal hernia in females.