Abstract: Radiation enteritis (RE) is an intestinal complication induced by radiotherapy for malignant tumors of the abdomen and pelvis. RE presents as long-term, intermittent aggravation of hematochezia, tenesmus, along with other symptoms such as serious intestinal perforation and obstruction. RE can cause serious damage to the patient's body and mental health and puts a large burden on the economy. The use of radiotherapy has been increasing with the rise in the incidence of abdominal and pelvic tumors; as a result, the occurrence of RE cases increases each year. Although the diagnosis of RE can be mainly based on medical history, radiology, endoscopy, and histologic features, differential diagnosis may sometimes become difficult. In addition, current RE management includes medical treatment, endoscopic treatment, and surgery, but there is no treatment startegies supported by high level evidence. To improve awareness as well as to discuss diagnosis and treatment strategies for this condition, this review summarizes the latest research advances in understanding of the risk factors, clinical manifestations, diagnosis, and treatment of RE.