Objective To explore the effect of narrow band imaging on the clinical outcomes of patients with high grade intraepithelial neoplasia in gastric mucosa.MethodsFrom June 2006 to June 2016, 96 patients of gastric high-grade intraepithelial neoplasia were enrolled in the study. All patients were divided into control group and observation group using a random number table method, 48 cases in each. In control group, patients were treated with endoscopic submucosal dissection treatment, while in observation group, patients were treated with narrowband imaging combined with endoscopic submucosal dissection treatment. The operation time, pathological type and occurrence of complications of the two groups were compared.Results The operation time, positive margin rates in observation group were lower than that in control group, while tumor diameter, one en bloc resection rate and curative resection rate was higher, the difference was statistically significant (P < 0.05). Pathological type: observation group includes 27 cases of HGIN, 15 cases of focal HGIN and 6 cases of high-moderately differentiated adenocarcinoma;while in control group, including 1 case of LGIN, 33 cases of HGIN, 11 cases of focal HGIN and 3 cases of high-differentiated adenocarcinoma patients, the difference was not statistically significant (P > 0.05). Overall incidence of complications in observation group and control group were 6.25% and 22.92% respectively; which shown observation group has significantly lower rate than control group, the difference was statistically.Conclusion Narrow-band imaging combined with endoscopy in the treatment of gastric neoplasia in patients with high-grade intraepithelial lesions can significantly improve the cure rate and complete resection en bloc resection rate, shorten the operation time, reduce the incidence of complications.