Abstract： Objective： To observe the effect of the therapy of Qingre Zaoshi Zhixie tang combined with mesalazine enteric-coated tablets on patients with ulcerative colitis(UC) of internal accumulation of damp-heat type. Methods：A total of 90 patients with UC in active stage were selected and divided into the control group and the treatment group according to the random number table method， with 45 cases in each group. The control group was treated with oral administration of mesalazine enteric-coated tablets，and the treatment group was additionally treated with Qingre Zaoshi Zhixie tang based on the treatment of the control group. Both groups were treated for eight weeks. The clinical effects in the two groups were compared. Before and after treatment，the changes in the scores of main symptoms，including diarrhea，abdominal pain， stool containing pus and blood and abdominal urgency with rectal heaviness， and the scores of intestinal mucosa under colonoscopy were compared between the two groups. The recurrence rates in the two groups after one year were followed up and observed. Results：After eight weeks of treatment，the total effective rate was 95.56% in the treatment group，and was 82.22% in the control group，the difference being significant(P＜0.05). After eight weeks of treatment，the scores of main symptoms， including diarrhea， abdominal pain， stool containing pus and blood and abdominal urgency with rectal heaviness，in the two groups were decreased when compared with those before treatment，and the above four scores in the treatment group were lower than those in the control group，differences being significant(P＜0.05). After eight weeks of treatment， the scores of intestinal mucosa under colonoscopy in both groups were decreased when compared with those before treatment， and the scores in the treatment group were lower than those in the control group， differences being significant(P＜0.05). The clinical effective patients，with 43 cases in the treatment group and 37 cases in the control group， were followed up for one year，and the recurrence rate was 23.26%(10/43) in the treatment group and 45.95%(17/37) in the control group， the difference being significant(χ 2=4.58， P＜0.05). Conclusion： The therapy of Qingre Zaoshi Zhixie tang combined with mesalazine enteric-coated tablets has a definite curative effect on patients with UC of internal accumulation of damp- heat type， which can alleviate the clinical symptoms， promote the recovery of intestinal mucosa and reduce the recurrence rate.