To investigate clinical efficacy and safety of the Chaihu Guizhi Ganjiang Decoction for patients with ulcerative colitis.Methods:Sixty-two patients with ulcerative colitis in our hospital were randomly divided into experimental and control groups, which were given Chaihu Guizhi Ganjiang Decoction or sulfasalazine pyridine tablets respectively. Clinical efficacy was evaluated by scoring the symptoms after treatment, and result of colonoscopy. Reoccurrence and the incidence of adverse reactions were followed up 1-year post treatment.Results:Experimental group have shown significantly better results than the control group (P<0.05) regarding effective rate, abdominal bloating score, abdominal pain score, recurrence rate and incidence of adverse reactions.Conclusion:Chaihu Guizhi Ganjiang Decoction is effective treatment for ulcerative colitis especially for relieving abdominal pain and bloating. It has lower recurrence and lower incidence of adverse reactions compared to sulfasalazine pyridine, therefore it’s recommendable in clinic practice.