A 55-year-old woman suffered from upper abdominal pain for two months and remained refractile against the anti-ulcer regimen. The palliative gastrectomy specimen revealed multiple shallow ulcerations on the thickened mucosal folds mainly in the antrum and body along the greater curvature where multiple, whitish nodules were found in the submucosa. Microscopically, individual submucosal nodules clearly corresponded to the necrotizing granulomatous vasculitis which were featured with diffuse fibrinoid necrosis of arterial walls accompanying granuloma formation and heavy infiltration of neutrophils, eosinophils, histiocytes and giant cells. Similar vasculitic lesions involved venules and arterioles. There were scattered vasculitic changes in the liver biopsy specimens and omentum. There were no clinical presentations or serological support of systemic involvement including systemic lupus erythematosus, Henoch-Schoenlein purpura, cryoglobulinemia or Churg-Strauss granulomatous vasculitis. We conclude that this is a hitherto undescribed primary necrotizing granulomatous vasculitis predominantly involving the stomach.