Objective Analysis on the effect of Shenling Baizhu powder on ulcerative colitis patients serum SOD and MDA levels. Methods 94 cases of ulcerative colitis patients in our hospital， were randomly divided into the observation group of 49 cases， 45 cases in the control group， the control group was given the salad Qin granule treatment， the observation group in the control group were given with modified shenglingbaizhusan， two groups were treated for 6 months， followed up for 6 months. The clinical efficacy of the two groups， the changes of serum SOD and MDA， the change of serum CRP， and the recurrence rate of follow-up were compared. Results The clinical effect of the observation group was significantly better than that of the control group（P<0.05）. After treatment， serum SOD increased significantly and MDA decreased significantly in two groups（P<0.05）. After treatment， SOD in observation group was higher than that in control group and MDA was lower than that in control group（P<0.05）. After treatment， the serum CRP decreased significantly in the two groups（P<0.05）， and the observation group was lower than that of the control group（P<0.05）. The recurrence rate of the patients in the observation group was significantly lower than that of the control group（P<0.05）. Conclusion Modified SHENLINGBAISHU Mesalazine SR Granules combined treatment of ulcerative colitis has significant clinical efficacy， and can effectively reduce the recurrence rate of the patients after treatment， the mechanism may be related to scavenging oxygen free radicals and reduce the inflammatory reaction， which is worthy of clinical promotion.