【Abstract】 Objective To investigate the effects of traumatic hemorrhagic shock on serum Dlactic acid, diamine oxidase and endotoxin and their effects on intestinal mucosal barrier function in rats. Methods Fifty adult male SpragueDawley rats were selected and randomly divided into control group (n=10), 1h shock group (n=10), 4h shock group (n=10), 8h shock group (n=10) and16h shock group (n=10). After the traumatic hemorrhagic shock model was established in rats, colorimetric assay was used to measure the DAO activity in rat serum. The endotoxin and Dlactic acid levels in rat serum were determined by spectrophotometry. Rat ileum tissue was harvested and the histopathological changes were observed. Venous blood and ileal tissue were collected at the same time points in the control group and the shock 1h group for detection and observation. Results Dlactic acid, Diamine oxidase and endotoxin levels in each group were statistically different. In the control group, the intestinal epithelium was structurally intact and no villus was absent and the morphology was normal. In the observation group, the intestinal mucosal structure was intact and the intestinal villi were irregular in the 1h shock group; Part of the intestinal epithelium was shed in the 4h shock group, with local edema and no obvious inflammatory cell infiltration; The epithelial shedding of the 8h group was increased, and the local edema was obvious. There was obvious inflammatory cell infiltration in the lamina propria; The epithelial tissue in the 16h group was severely shedding, and the edema was severe. The infiltration of inflammatory cells in the lamina propria was more obvious than that in the 8h group. Conclusion In the early stage of traumatic hemorrhagic shock, intestinal barrier dysfunction occurs. Serum Dlactic acid, DAO and endotoxin are sensitive indicators for the early diagnosis of intestinal mucosal injury, and their levels are positively correlated with the pathological changes of intestinal mucosal tissues.