Abstract：Objective：To observe the clinical effect of Sishen pills and Shenling Baizhu powder combined with mesalazine for ulcerative colitis and its effect on intestinal flora and intestinal barrier function. Methods：A total of 60 cases of patients with ulcerative colitis of kidney yang deficiency type were randomly divided into the control group and the Chinese medicine group，30 cases in each group. The control group was given oral administration of mesalazine enteric- coated tablets，and the Chinese medicine group was additionally given Sishen pills and Shenling Baizhu powder based on the treatment of the control group. The Chinese medicine syndrome scores， modified Mayo endoscopic scores， intestinal flora and intestinal barrier function before and after treatment and the curative effect of Chinese medicine syndrome after treatment in the two groups were observed. Results：After treatment，the total effective rate was 93.3% in the Chinese medicine group，higher than that of 70.0% in the control group(P＜0.05). After treatment， Chinese medicine syndrome scores， modified Mayo endoscopic scores，the number of escherichia coli and the levels of endothelin(ET)，D-lactate and diamine oxidase(DAO) in serum in the two groups were decreased when compared with those before treatment(P＜0.05)， and the numbers of bifidobacterium and lactobacillus were increased(P＜0.05). Chinese medicine syndrome scores，modified Mayo endoscopic scores， the number of escherichia coli and the levels of ET， D- lactate and DAO in serum in the Chinese medicine group were lower than those in the control group(P＜0.05)，and the numbers of bifidobacterium and lactobacillus were higher(P＜ 0.05). Conclusion： Sishen pills and Shenling Baizhu powder combined with mesalazine can effectively improve the clinical symptoms of patients with ulcerative colitis of kidney yang deficiency type， and can achieve curative effect by increasing intestinal available bacteria，regulating intestinal flora structure and promoting repair of intestinal mucosal barrier.