Abstract: Objective: To investigate the effects of retention enema modified on ulcerative colitis. Methods: Thirty patients with ulcerative colitis were randomly divided into observation group(15 cases) and control group(15 cases) . The control group were treated with traditional retention enema and the observation group with retention enema modified. The therapeutic effects of two groups were observed. Results: The retention time and therapeutic efficacy of rectal solution in observation group were better than that of the control group(P ＜ 0. 01) . The hospital stays of two groups had not statistical significance(P ＞ 0. 05) . Conclusions: Therapeutic efficacy of retention enema modified is good, and which is simple, economy,patient satisfaction. The method can be easily mastered and operated.