Functional magnetic resonance imaging is a relatively new imaging technique in clinic. It plays an important role in the accurate radiotherapy of esophageal cancer in recent years. Functional magnetic resonance imaging can not only improve the accuracy of radiotherapy target, but also predict the effect of radiotherapy and evaluate the prognosis of radiotherapy. In this paper, the application of functional magnetic resonance imaging in radiotherapy of esophageal carcinoma by different tumor centers at home and abroad is reviewed.