Eosinophilic gastroenteritis is a rare disease occurring especially in children, and shows various nonspecific presentations with infiltration of eosinophils in the gastrointestinal organs. The pathophysiology of eosinophilic gastroenteritis is not yet clearly known, but allergic reactions are suspected to be related with the disease. Eosinophilic gastroenteritis is categorized into the mucosal, muscularis and subserosal types based on which layer of the intestinal wall is involved. There are different clinical manifestations according to the involved layer. Most cases to date have responded well to steroid therapy. In this study, we diagnosed and treated a case of non-IgE-mediated, subserosal eosinophilic gastroenteritis in a child with abdominal pain, diarrhea and ascites.