Abstract: Esophageal carcinoma is one of the most severe cancers; while,radiotherapy is one of the most important treatment modalities.However,traditional imaging such as CT and endoscopic ultrasound (EUS) can only provide anatomical information during radiotherapy simulation,orientation and evaluation of the therapeutic effect of chemoradiotherapy.But in recent years,18F-FDG PET/CT with integration of functional and anatomical information has been used more and more widely in tumor diagnosis,staging,and evaluating therapeutic effect and prognosis.This paper summarizes recent progress in the application of 18F-FDG PET/CT for diagnosis,staging,and radiotherapy of esophageal cancer.