Eight patients subjected to surgery for ulcerative colitis were followed up 1-27 years. Of eight, 3 patients received Kock's continent ileostomy and 5 patients end ileostomy. The survey was performed mainly in terms of emptying frequency, the internal pressure and the capacity of the ileostomy. The patients with continent ileostomy empty their reservoirs one to four times a day, while the patients with end ileostomy change the ileostomy bags four to ten times a day. In patients with Kock's ileostomy, high pressure zone was observed at 3 to 6 cm proximal to the stoma corresponding to the site of the nipple valve. The pressure of the nipple valve showed higher than the internal pressure of the reservoir. When the internal pressure at the site of 10 cm proximal to the stoma was measured after end ileostomy, it increased proportionally to the amount of infused saline. Infusion of 50 ml of saline induced its evacuation from the stoma without causing any sensation of fullness to the patients. The patients with Kock's ileostomy announced sensation of fullness when 80% of the maximal capacity of the reservoir was filled with saline. This sensation of fullness made it easy for the patients to control emptying the reservoir. Therefore, we conclude that Kock's procedure should be more widely performed to ulcerative colitis when ileostomy is required.