Abstract: Blood acetylcholine content and cholinesterase activity were estimated in 49 patients with chronic gastritis and 20 patients with peptic ulcer. The changes observed in chronic gastritis were very similar to those in peptic ulcer, i. e. the increase in blood level of a cetylcholine accompanied the decrease in blood cholinesterase activity. Since the cholinergic nerve impulses stimulate both parietal cells and antral G-cells to secrete gastic acid, so vagotonia plays an important role in the pathogenes is of duodenal ulcer. whether the cholinergic mechanism does exist in the pathogenesis of chronic gastritis is not certain, Furher investigation is needed.