Thirty cases of gastric adenocarcinoma were examined immunohistochemically for expression of transforming growth factor-beta(TGF-beta) in order to analyze significant correlation with clinical stage and pathologic grade of gastric adenocarcinoma. Specific immunostaining was clearly detected in the cytoplasm of the neoplastic cells. The TGF-,6 expression in the gastric adenocarcinoma is closely related to the depth of invasion, the degree of invasiveness and the presence of metastasis. Thus, we observed the stronger immunohistochemical. expression of TGF-beta in the deeper portion of invasion and in the invasive gastric adenocarcinomas with the lymph nodal metastasis than in the superficial portion of invasion and in those without the lymph nodal metastasis. There results suggest that the transforming growth factors expression in carcinoma cells may play an important role in the carcinomatous invasion resulting in metastasis.