Food protein-induced enterocolitis syndrome (FPIES) is an under-recognized and frequently misdiagnosed non-IgE-mediated gastrointestinal food hypersensitivity disorder. We describe the first case of FPIES only to wheat confirmed by an oral food challenge (OFC). The male patient, who was breast fed for the first 2 months, and then was feeding with cow's milk-based formula until he became 4.5 months old, was given a tarhana soup (wheat and yoghurt) for the initial food trial. Two hours later, he started retching and vomited consecutively, suffering from watery diarrhea. He was taken to a medical center, where he was diagnosed acute gastroenteritis. He suffered from three more episodes after feeding wheat-containing foods. When the patient was 12 months old, an OFC with wheat was performed. Two hours after he had been challenged, he vomited repetitively, became lethargic, his systolic blood pressure dropped from 95 to 80 mm Hg and stool examination revealed eosinophils and leukocytes, which were negative before the challenge. The serum eosinophil count decreased from 460 to 270 mu L and the neutrophil count increased from 2,200 to 10,500 mu L at 6 h. The skin prick test with wheat extract, prick to prick test with whole wheat and serum-specific Ig E for wheat were negative. We conclude that FPIES can emerge with food in connection with eating habits or culture. In view of its potentially serious clinical course, it is critical to consider this diagnosis in young children presenting with acute onset of gastrointestinal symptoms or shock.