We present a 25 year-old woman who was examined for abdominal pain after uncomplicated spontaneous delivery. An intraabdominal hemorrhage was suspected and laparotomy was performed after the delivery. Postpartum spontaneous hemoperitoneum can be associated with vascular malformations, ectopic decidualization and avulsion of pelvic uterine adhesion band. Full exploration of abdominal cavity, including intraabdominal and retroperitoneal organs, revealed no source of hemorrhage. To best of our knowledge, this is a very rare case of idiopathic spontaneous hemoperitoneum at early postpartum period.