The susceptibility to cancer in the vagotomized stomach which was assigned either to selective vagotomy (SV) or selective proximal vagotomy (SPV) was studied by gastric carcinoma model of male Wistar rat on N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) administration. Predilection for cancer of the remnant stomach was also studied. Four groups of the rats submitted to either one of the SV, SPV, antrectomy (Billroth-I reconstruction) or control (simple laparotomy) group, were prepared. The techniques of SV and SPV in rat was originally developed. MNNG in drinking water was given as carcinogen. Gastric acid output, gastric stasis, serum gastrin levels together with the number and the invasiveness of the atypical glands those were recognized in the glandular stomach of rats were examined. The results were as follows: (1) the reduction rate of gastric acid output was the most conspicuous at antrectomy group followed by SV and SPV groups, (2) gastric stasis was observed in almost the same degree in SV and SPV groups, (3) serum gastrin level was the highest in SV group followed by SPV, control and antrectomy groups in this order and (4) the susceptibility to malignancy was significantly high at SV group but not high at SPV and antrectomy group as compared with control group.