Hemoperitoneum is a rare complication of uterine leiomyomas. Increased abdominal pressure during mechanical stress (i.e., trauma, intercourse, or menstruation) may lead to the rupture of superficial veins overlying the leyomioma. A 39-year-old woman presented with intra-abdominal bleeding without any evidence of mechanical stress. The bleeding was caused by a uterine superficial vein overlying a subserosal leiomyoma. After hysterectomy, histopathologic findings revealed diffuse venous ectasia throughout the whole uterus. Diffuse myometrial venous congestion should be considered a possible predisposing factor to spontaneous rupture of the superficial vessel