Objective To investigate protective effects of preconditioning combined with post adaptation on cerebral ischemia / reperfusion injury in rats. Methods 50 clean grade male SD rats were randomly divided into sham operation group, model group, pre adaptation group, post adaptation group and preconditioning + post adaptation group, with 10 rats in each group. except sham operation group, the rats were made into cerebral ischemia / reperfusion injury model. After reperfusion 48h, the neurological function, cerebral infarction, brain tissue oxidative stress injury biochemical indicators and neuronal apoptosis in rats were observed. Results The nerve function defect score of model group after reperfusion 12, 24 and 48h was significantly higher than that of other groups (P＜0.05). The nerve function defect score of preconditioning + post adaptation group after reperfusion 12, 24 and 48h was the lowest among the groups (P＜0.05). The infarct volume of preconditioning + post adaptation group (100.41±33.26 mm3) was significantly lower than that of model group, preconditioning group and post adaptation group (P＜0.05). The volume of cerebral infarction in the preconditioning group and the post adaptation group were lower than that of the model group (P＜0.05). The superoxide dismutase (SOD) activity of Sham operation group was significantly higher than that in the model group (P＜005). The malondialdehyde (MDA) activity of Sham operation group was significantly lower than that in the model group (P＜0.05). The SOD activity of post adaptation group and preconditioning + post adaptation group were higher than that in the model group, but MDA of post adaptation group and preconditioning + post adaptation group were lower than that in the model group (P＜005). The number of apoptotic cells of Sham operation group was significantly lower than that in the model group (P＜0.05). Conclusion Preconditioning and post adaptation can protect the cerebral ischemia / reperfusion injury in rats, and the combined application can further strengthen the protective effect.