Abstract：Objective：To observe the curative effect of the therapy of Qingxin Xiepi San combined with Probiotic Aloe Vera Fermentation Gel on recurrent oral ulcer (ROU). Methods： A total of 88 ROU patients were selected and divided into the control group and the study group according to random number table method，with 44 cases in each group. The control group was treated with Probiotic Aloe Vera Fermentation Gel， and the study group was treated with Qingxin Xiepi San combined with Probiotic Aloe Vera Fermentation Gel. The clinical effects， improvement time of symptoms and recurrence rates， and the changes of immune function and inflammatory factors [C-reactive protein (CRP)， interleukin-6 (IL-6)] before and after treatment were compared between the two groups. Results： After treatment， the disappearance time of ulcer exudatie disappe ars， edema and pain and healing time of ulcer in the study group were respectively shorter than those in the control group，the differences were significant (P＜0.05). After treatment， the levels of CD3+ ， CD4+ and CD4+/CD8+ in the two groups were increased when compared with those before treatment (P＜0.05)，and the above three levels in the study group were higher than those in the control group (P＜0.05). After treatment，the IL-6 levels in the two groups were elevated when compared with those before treatment (P＜0.05)， and the CRP levels were decreased when compared with those before treatment (P＜0.05)；the IL-6 level in the study group was higher than that in the control group (P＜0.05)， and the CRP level was lower than that in the control group (P＜0.05). The clinical effective rate was 93.18% in the study group and 75.00% in the control group，the difference being significant (P＜0.05). The recurrence rate was 14.63% in the study group and 45.45% in the control group， the difference being significant (P＜0.05). Conclusion： The therapy of Qingxin Xiepi San combined with Probiotic Aloe Vera Fermentation Gel can improve the clinical symptoms of ROU patients， mitigate the inflammatory responses，improve the immune function and reduce the recurrence rate.