Abstract：Objective：To observe the clinical effect of Buzhong Yiqi Decoction combined with Infliximab for active Crohn disease and its effect on the immune function of patients. Methods：A total of 86 cases of patients with active Crohn disease were divided into the control group and the observation group according to the random number table method， with 43 cases in each group. The control group was treated with Infliximab，and the observation group was additionally treated with Buzhong Yiqi Decoction based on the treatment of the control group. Clinical effects，mucosa healing rates，recurrence rates and the incidence of adverse reactions were compared between the two groups. Changes in Crohn Disease Activity Index (CDAI)， Crohn Disease Endoscopic Index of Severity(CDEIS) and indexes of immune function in the two groups before and after treatment were observed. Results： The total effective rate was 95.35% in the observation group，higher than that of 79.07% in the control group(P＜0.05). The mucosa healing rate was 88.37% in the observation group，higher than that of 69.77% in the control group(P＜0.05). The recurrence rate was 5.56% in the observation group，lower than that of 35.71% in the control group(P＜0.05). After treatment，the scores of CDAI and CDEIS in the two groups were decreased when compared with those before treatment(P＜0.05)， and the two scores in the observation group were lower than those in the control group(P＜0.05). After treatment， the levels of CD3 + and CD4 + in serum in the two groups were decreased when compared with those before treatment(P＜0.05)，and the levels of CD4+/CD25+ regulatory T cell(Treg) in serum were increased when compared with those before treatment(P＜0.05)；the levels of CD3+ and CD4+ in serum in the observation group were lower than those in the control group(P＜0.05)，and the levels of CD4+/CD25+Treg in serum were higher than that in the control group(P＜0.05). The incidence of adverse reactions were 9.30% in the observation group and 4.65% in the control group， there being no significance in the difference(P＞0.05). Conclusion： Buzhong Yiqi Decoction combined with Infliximab for active Crohn disease can enhance the curative effect， reduce recurrence， and improve the immune function of patients with high safety.