Gastrointestinal bleeding from Meckel's diverticulum resulted in small bowel obstruction by thrombus in two patients with acute myelogenous leukemia during bone marrow aplasia and recovery from induction chemotherapy. Although gastrointestinal symptoms and complications are common in acute leukemia, these two cases are unique and describe a new syndrome that requires prompt recognition and surgical intervention. The complication of localized bowel obstruction by intraluminal thrombus is heretofore unreported.