Capsule endoscopy is a relatively new technology that has allowed gastroenterologists to visualize the mucosa of the small intestine. This technology is playing an expanding role in both adult and pediatric gastroenterology. In this report, we present an 8-yr-old child following allogeneic hematopoietic cell transplantation who developed large volume bloody diarrhea requiring multiple packed red blood cell transfusions that was resistant to aggressive therapy for GVHD. The capsule endoscopy performed on this patient provided significant information not provided by upper endoscopy and colonoscopy that allowed for successful treatment changes. This case demonstrates that capsule endoscopy is a diagnostic tool that may play an important role in the assessment of patients, including children, with possible GVHD.