The patients was 49-year-old man. Endoscopic examination showed a diffuse elevated lesion with irregular ulcer at the greater curvature of the gastric anglus in September 1991. With the histologic findings of biopsy specimens, we made a diagnosis of localized gastric amyloidosis. In October 1993, this lesion was re-diagnosed as gastric plasmacytoma with endoscopic biopsy, and total gastrectomy with splenectomy was performed in May 1994. The tumor was histopathologically gastric plasmacytoma and immunohistochemical study revealed to be classified in lgA/ type. A part of the tumor and amyloid deposits extended to the submucosal layer. This case suggests the possibility of the association between gastric plasmacytoma and amyloid production.