Eight patients had gastrocolic fistulas depicted on barium studies at the authors' hospital during a 10-year period between 1982 and 1992. Seven of those patients (88%) had benign disease, including aspirin-induced gastric ulcers of the greater curvature (n = 4), granulomatous colitis (n = 1), tuberculosis (n = 1), and a penetrating anastomotic ulcer after partial gastrectomy (n = 1). The remaining patient had a malignant gastrocolic fistula caused by carcinoma of the transverse colon. Two patients (25%) experienced classic symptoms of gastrocolic fistulas (ie, feculent vomiting or foul-smelling eructations), but the other six (75%) experienced abdominal pain or other nonspecific clinical findings. In the four patients who were taking aspirin, upper gastrointestinal examinations revealed giant penetrating ulcers of the greater curvature that communicated with the superior border of the transverse colon via a fistula. Three of these patients exhibited marked clinical improvement after conservative medical treatment and did not need surgery. This experience suggests that aspirin-induced gastric ulcers of the greater curvature have become a more common cause of gastrocolic fistulas than is carcinoma of the stomach or transverse colon.