Objective To evaluate the effect of de-splanchnic circulation of the stomach (DSCS) on ultramicrostructure of gastric mucosa and submucosal microcirculation in prehepatic portal hypertensive canine models. Methods Twelve prehepatic portal hypertensive canine models were established by half constriction and silk line chronic embolization of the portal vein. The esophageal varices and collateral circulation were observed by venography after 4 weeks. Dogs with established model were divided into pericardial devascularization group and DSCS group randomly. Esophageal variceal pressure (VP) was measured when the abdoman was open immediately before the abdoman was closed and 4 weeks after the operation respectively. The liver function was also tested preoperatively and 4 weeks postoperatively. The ultrastructure of gastric mucosa and submucosal microcirculation was observed by transmission electron microscope.Results The VP decreased significantly from (22. 1 ± 0.9 ) cm H2O to (17. 8 ± 0. 4) cm H2O after DSCS ( P ＜ 0. 01 ). There were no obvious different changes in the liver function preoperatively and postoperatively ( P ＞ 0. 05 ) in pericardial devascularization group. The microvillus of gastric epithelium cells were interrupted and fell off and that microvillus significantly reduced. Moreover, it was also shown that the basal lamina of submucosal veinule endothelial cells were uneven thick and discontinuous and that red blood cells could be obviously gathered in the endothelial cells interspace. While there were less severe damages in the gastric musosa epithelia and submucosal venule endothelial cells in DSCS group. Conclusions DSCS procedure can significantly decrease espophageal variceal pressure and improve the ultramicrostructure of gastric mucosa and submucosal microcirculation in canine models with prehepatic portal hypertension.