AimTo study the effects of acute hyperglycaemia on Mitochondria Membrance Potential and Cytochrome c after AMI in rats without diabetes.MethodsWe ligated the left anterior descending coronary artery of fourty male SD rats to build the models of AMI.Then,These animals were randomly divided into 4 groups: CON group, HG1 group, HG2 group and insulin group;And another ten male SD rats were used as Sham group, Blood glucose levels were monitored throughout the experiment.Apoptotic index（AI）,Mitochondria Membrance Potential, mitochondria and endochylema Cyt-c were measured.ResultsCompared with SHAM group, the AI and endochylema Cyt-c were significantly higher in other groups；The Mitochondria Membrance Potential and the expression of mitochondria Cyt-c were significantly lower in other groups. The things were diametrically opposed in the HG2 group. The Mitochondria Membrance Potential and the expression of Cyt-c were not significantly different in CON group,HG1 group and insulin group.ConclusionAcute hyperglycaemia after AMI has significant influences on apoptosis in rats by way of Mitochondria, We can protect cardiac muscle cell by injecting insulin which can reduce blood glucose.