Esophageal cancer was the fifth most common incident cancer and the fourth most lethal cancer in China. Radiation therapy was one of the most important treatment for esophageal cancer. The incidence of malnutrition in esophageal cancer is the highest in all malignant tumors. Because of swallowing obstruction due to primary tumor and radiation therapy related complications, the incidence of malnutrition in esophageal cancer patients treated with radiaotherapy was higher. Malnutrition might reduce the radiation sensitivity and precision, increase adverse reactions, affect the completion of the radiation, reduce the survival and quality of life. Nutritional therapy played an important role for the treatment and prognosis of esophageal cancer treated with radiotherapy. More and more oncologists payed attention to the nutritional therapy. For the esophageal patients with the risk of malnutrition, nutritional therapy was an indispensable part of combined modality therapy during radiotherapy. There was no criteria or specification about the method of nutritional therapy for esophageal cancer treated with radiotherapy. The nutritional therapy contained enteral nutrition, parenteral nutrition and partal enteral combined parenteral nutrition. This article mainly expounded the purpose, indications, optimal time, therapeutic approach, nutrients, nutrition related complication prevention and treatment and home nutritional therapy, which would give some reference and advice to the radiation oncologists when conducting nutritional therapy.