In an attempt to evaluate the effect of induced hypertension chemotherapy (IHC) using angiotensin II human, histopathological analysis was performed on stomachs excised from thirteen patients who had advanced gastric carcinoma and were submitted to presurgical cancer chemotherapy. IHC was introduced in randomly chosen eight patients and, in the remaining five patients, chemotherapy was designed under conventional conditions. A common regimen comprising 5-fluorouracil, adriamycin, mitomycin C was applied in both the IHC and non-IHC groups. The clinical effect in these patients, assessed prior to surgery, gave rise to the confirmation of three CR patients in the IHC group, while in the non-IHC, PR was the highest score. Histological examination illuminated a patient in the IHC group in whom no viable carcinoma cell proved to remain in the excised stomach, a state meeting the requirements for the highest (Grade 3) effectiveness according to the standard given by the Japanese Research Society for Gastric Cancer. In another two patients of the same group, the effect was Grade 2, i.e., the degeneration and loss of carcinoma cells in the major part of tumor. In contrast, the effect in the non-IHC group was Grade 1b at the highest, where chemotherapy-associated degeneration and necrosis did not predominate over one third of tumor area. Thus, the mean histological score was apparently higher in the IHC than in the non-IHC group, with a difference significant at p less than 0.05 by Wilcoxon's test. Patients clinically evaluated as effective tended to be so pathologically as well, as shown by Spearman's rank correlation test which gave a significant correlation between the clinical and pathological scores.