The effect of verapamil on gastric acid secretion and serum gastrin in the pylorus ligated rats was studied. The results were as follows; 1) The volume of gastric juice was increased in the verapamil-histamine group than in the histamine group. 2) The gastric acid output was decreased in the verapamil group and verapamil-histamine group than in the histamine group. 3) There was no statistical significance in serum gastrin concentration among each groups. Calcium-channel blocking agent inhibits the histamine-stimulated gastric acid secretion and dose not contribute on the serum gastrin concentration.