Abstract: Objective: To evaluate the value of endoscopic ultrasonography(EUS) in the preoperative TN staging of gastric cancer,and to improve its diagnostic level.Methods: The preoperative TN staging of gastric cancer diagnosed by pathology in 133 patients were identified by EUS,which was compared with the postoperative histopathological stage.Results: The overall accuracy rate of preoperative T staging of gastric cancer detected by EUS was 81.20%.The accuracy of T1 and T4 were high,whose were 91.67% and 85.0%,the accuracy of T2 and T3 were low,whose were 74.29% and 70.0%,respectively.There were too deep or too shallow phenomenon in the T staging,too deep in 8 cases and too shallow in 17 cases were found.The preoperative staging of gastric cancer detected by EUS was highly consistent with the postoperatively pathological staging(P<0.01).The overall accuracy rate of N staging identified by EUS was 78.95%,the accuracy rate of positive and negative lymph node were 66.10% and 89.19%,respectively,the differences of whose compared with the postoperatively pathological staging were statistically significant(P<0.05).Conclusions: Endoscopic ultrasonography can accurately identified the TN staging of gastric cancer,which can provide the basis in formulating the reasonable treatment.