Parasitic leiomyomas are a rare subtype of subserosal uterine leiomyomas and are mostly found incidentally. Diagnosis is challenging and treatment consists out of complete surgical resection. Cases are few in women without history of uterine surgery. In this extraordinary case, a 56-year-old menopausal female suffering from backache and abdominal swelling, was suspected to have a huge malignant ovarian tumor. She underwent a resection of the mass along with hysterectomy and bilateral salpingo-oöphorectomy. Histopathology revealed a gigantic leiomyoma of 19.1 kg in the broad ligament. This unique case suggests taking this diagnosis into account in future clinical cases presenting with large abdominal masses even without previous uterine surgery.