Eosinophilic gastroenteritis is an infrequent entity characterized by tissular eosinophilia that can affect different layers of the intestinal wall. This entity can affect any area of the digestive apparatus from the esophagus to the rectum. Clinical manifestations depend on the affected layers and range from barely perceptible symptoms to intestinal obstruction or ascites. We present the case of an 18-year-old woman who showed abdominal ascites as a rare form of presentation with difficult differential diagnosis with peritoneal carcinomatosis.