Abstract: Objective To explore the prevention and treatment effect of thalidomide combined trolamine cream retention enema on acute radiation proctitis， and the influence on the living quality. Methods From January 2015 to March 2017， 69 patients were randomly divided into experimental group （n=35） and control group （n=34）. All the patients were given concurrent chemoradiotherapy. The total dose of radiation was 50 Gy／25 f／5 w. Capecitabine was administered orally at the beginning of radiotherapy （1250 mg／m2， twice a day， d1-d14， 21 days as a cycle for 2 cycles）. Patients in experimental group received thalidomide （with initial dose of 100 mg／d orally） and retention enema with triethanolamine cream （triethanolamine cream 15 g and 100 ml warm normal saline for retention enema once a day until the end of radiotherapy）. The occurrence of acute radiation proctitis， the tolerance of concurrent chemoradiotherapy and the changes of Karnofsky score， sleep status， diet status and weight status were observed. Results The incidence of acute radiation proctitis in experimental group was 77.1%（27／35）， lower than 100.0%（34／34）of control group， and the level of acute radiation proctitis in experimental group was also lower than control group （P<0.05）. The radiation doses of acute radiation proctitis occured for the first time in experimental group was （36.4±5.6） Gy， higher than （13.6±3.7） Gy of control group （P<0.05）. In experimental group， the improvement rates of Karnofsky score， sleep status， diet status and weight status were 71.4%（25／35）， 94.3%（33／35）， 62.9%（21／35） and 51.4%（18／35），better than 2.9%（1／34）， 0（0／34）， 2.9%（1／34）and 5.9%（2／34）of control group （P<0.05）. The rates of radiotherapy interruption and the total course of radiotherapy in experimental group were lower than those in control group， while the complete cycles of chemotherapy in experimental group was more than that in control group （P<0.05）. No patient withdrew treatment due to severe side effects. Two patients in experiment group suffered from somnolence， and improved by symptomatic treatment. Conclusion Thalidomide combined with retention enema of triethanolamine cream can prevent and treat acute radiation proctitis caused by radiotherapy after radical resection of rectal cancer， as well as improve the quality of life.