Multiple myeloma is a clonal proliferation of plasma cells with multiple osteolytic lesions.Extramedullary dissemination of multiple myeloma in ovary is relatively uncommon.A 54-year-old female patient,diagnosed as multiple myeloma three years ago,was admitted to the hospital for the complaints of intermittent abdominal pain for three days.The vaginal gynecological ultrasound showed celiac solid mass.The emergent laparotomy showed a significantly enlarged right cystic ovary and the pathological reviews showed ovarian plasmacytoma.The final diagnosis of this patient was ovarian extramedullary plasmacytoma rupture and bleeding.