Summary:Two children with glycogen storage disease type 1B developed chronic inflammatory bowel disease. The first, a 7‐year‐old boy, had ileitis and later developed perianal disease. The second developed colitis by the age of 9 years; in both the features were consistent with Crohn disease. The children had neutropenia and neutrophil mobility defects characteristic of GSD‐1B. It is suggested that these neutrophil abnormalities are important in the pathogenesis of the bowel inflammation.