Acute abdominal pain with peritonitis due to sudden extravasation of lymph into the peritoneal cavity is a rare condition that is often mistaken for other causes of acute abdomen. The diagnosis of spontaneous chylous peritonitis is rarely suspected preoperatively, usually misdiagnosed with diverse common surgical emergencies. We report the case of an 81 year old female who presented with typical symptoms of acute abdomen, presumed as acute mesenteric ischemia. The diagnosis of chylous peritonitis was established during laparoscopy and treatment consisted of low fat diet and octreotide.