In 38 rats, a substitute stomach was prepared through transplantation of the ileocaecal intestinal portion following total gastrectomy. 47% of rats tolerated the operation. The survival rate of the tolerated rats for 360 days after the surgery was 16%. Their body weight corresponded to 77% of that in the untreated control rats on the 360th day after the operation. Compared to other conventional methods of total gastrectomy and reconstruction, this method is quite outstanding. From this experimental fact, the preparation of a substitute stomach through transplantation of the ileocaecal intestinal segment seems possible to supplement a part of the defects in the agastric syndrome accompanying total gastrectomy for a prolonged period.