Abstract： Objective:To investigate the clinical effect and action mechanism of Smecta and Kangfuxin mixture retention enema combined with hyperbaric oxygen (HBO) in the prevention of radiation proctitis (RP) after radiotherapy for cervical cancer.Methods:A total of 92 patients with RP after radiotherapy for cervical cancer admitted to Chongming Branch of Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine from January 2016 to December 2019 were selected and divided into observation group and control group according to their treatments, with 46 cases each. The control group was treated with Smecta and Kangfuxin mixture retention enema, and the observation group was treated with HBO on the basis of the treatment of the control group. The incidence, time of occurrence, and classification of acute and chronic RP of both groups were recorded. The results of colonoscopy were observed and evaluated by the Viennese colonoscopy score. The levels of immunoglobulin IgG, IgM, and IgA in the two groups before and after treatment were detected by immunoturbidimetric method. The levels of interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) were detected by enzyme-linked immunosorbent assay (ELISA), and the levels of C-reactive protein (CRP) was detected by fluorescence method.Results:The incidence of acute RP after radiotherapy in the observation group was significantly lower than that in the control group, and the average occurrence time of RP in the observation group was significantly delayed than that in the control group ( P<0.05). The incidences of grade 1-2, grade 3-4 RP, and the total incidence of acute and chronic RP in the observation group were significantly lower than those in the control group ( P<0.05). The patients with 0-2 points of Viennese colonoscopy scores in the observation group were significantly more than those in the control group, and the patients with 3-5 points were less than those in the control group, the differences were statistically significant ( P<0.05). After treatment, the levels of IgG, IgM, and IgA in the observation group were significantly higher than those in the control group, while the levels of TNF-α, IL-6, and CRP in the observation group were significantly lower than those in the control group ( P<0.05). Conclusion:Smecta and Kangfuxin mixture retention enema combined with Hyperbaric oxygen (HBO) can delay and reduce the occurrence of radiation proctitis and relieve the clinical symptoms of cervical cancer patients after radiotherapy. The mechanism may be achieved by improving the immune function and reducing the level of inflammatory factors.