The anticardiolipin or antiphospholipid antibody syndrome is characterized by an increased incidence of venous and arterial thromboses. This syndrome may occur in association with systemic lupus erythematosus or independently. Gastroenterological manifestations have included Budd-Chiari syndrome, hepatic infarction, esophageal necrosis with perforation, intestinal ischemia and infarction, pancreatitis, and colonic ulceration. We report a 39-yr-old man with antiphospholipid antibody syndrome complicated by adrenal insufficiency secondary to bilateral adrenal infarction who presented with severe epigastric pain. Endoscopic evaluation disclosed progressive gastric ulceration with necrosis in the distal body. Angiography revealed no vasculitis. Because of intractable pain despite intravenous anticoagulation and narcotic analgesia, the patient was taken to surgery, and an antrectomy with Billroth II gastrojejunostomy was performed. Histological examination revealed widespread vascular occlusive disease involving veins, small arteries, and arterioles present in all layers of the stomach and the perigastric fat consistent with the vasculopathy of the antiphospholipid antibody syndrome. Treatment with high intensity oral anticoagulation and corticosteroids resulted in clinical and endoscopic improvement. This case report extends the gastroenterological manifestations of the antiphospholipid antibody syndrome to include giant gastric ulceration and emphasizes the importance of anticoagulation in treatment.