Objective To evaluate the effects of ischemia time on intestinal ischemia-reperfusion injury in a rat model by assessing oxidative damage and histopathology, to provide optimal modeling conditions and basic data for future studies. Methods Twenty-four male SD rats were divided randomly into a sham operation group, 30 min ischemia group, 1 h ischemia group and 2 h ischemia group. Ischemia-reperfusion injury models were induced by ischemia of the superior mesenteric artery for the noted time, followed by reperfusion for 4 h. After resumption of the blood supply, the rats were euthanized. Than,take 10% intestinal tissue homogenate and test with kit,test the levels of superoxide dismutase (SOD), malondialdehyde (MDA), glutathione peroxidase (GSH-Px) and glutathione were determined. The morphology of the intestinal tissue was observed by hematoxylin and eosin staining, and villus height and mucosa thickness were measured. Results SOD, GSH-Px and MDA were all significantly increased in the 30 min and 1 h ischemia groups compared with the sham operation group (P<0. 05). Inflammatory cell infiltration was aggravated and the pathological Chiu’s score was significantly increased in the ischemia groups (P<0. 05). In addition, 1 h and 2 h of ischemia significantly reduced the villus height and mucosal thickness in the small intestine (P<0. 01), while 2 h of ischemia could cause death(death rate 33. 3%). Conclusions An intestinal ischemia-reperfusion model established by 1 h ischemia and 4 h reperfusion had the most ideal oxidation index and intestinal tissue morphology, and is thus suitable for disease research and drug development.