Radiation proctitis denotes the radiation damage of rectum caused by radiotherapy to pelvic malignancy. The clinical practices of radiation proctitis should be fully considered from diagnosis, treatment and prevention. In order to determine appropriate treatment strategies, the diagnosis of radiation proctitis should be based on clinical symptoms, endoscopic findings, imaging and histopathology to assess severity of symptoms and stage of disease. In terms of treatment decisions, non-surgical interventions are generally applied to relieve major symptoms and avoid serious complications. Diverting colostomy and restorative resection are the main surgical treatments for patients with recurrent symptoms. In terms of prevention, radiation proctitis should be prevented by improvement of radiotherapy technology, physical protection and prophylactic medication. This guide aims to provide guidance for the clinical practices of radiation proctitis in China.