To assess the value of fluorine-18 fluorodeoxyglucose (FDG)-positron emission tomography (PET) in carcinoma of the esophagogastric junction.From December 1998 to April 2002, 27 patients were imaged with FDG-PET and FDG avid masses in the esophagogastric junction were found in every patient. FDG-PET data was analyzed by visual method and standardized uptake value (SUV). FDG-PET results were compared with pathological results and follow-up survey.16 carcinomas of the esophagogastric junction and 11 non-specific FDG-avid masses of normal stomach were all considered malignant by visual method. Maximum and mean Standard uptake value (SUV) of cancer were 6.71 +/- 2.75 and 5.46 +/- 2.31, respectively; SUVmax and SUVmean of non-specific FDG avid mass were 2.99 +/- 0.67 and 2.38 +/- 0.51 respectively; SUV of cancer was higher than that of non-specific FDG avid mass (Z = -4.171, Z = -4.195, P < 0.01).FDG-PET has limited value in differentiating carcinoma of the esophagogastric junction from non-specific FDG avid mass of normal stomach.