Aim To study the expression of hypoxia-inducible factor-1α(HIF-1α) in myocardial infarction rats and the role of protein kinase C (PKC) in signal pathway of hypoxia-inducible factor-1α gene expression. Methods 32 healthy male Wistar rats were divided into four groups:ischemic preconditioning group,simple myocardial infarction group,ischemic preconditioning plus protein kinase C inhibitor group and sham-operation group. Rats in treated groups received ligation of the proximal left anterior descending coronary artery to induce acute myocardial infarction. The sham-operation group dont take ligation of coronary artery. In ischemic preconditioning plus PKC inhibiter group,rats were injected with the protein kinase C inhibitor (chelerythrine,5 mg/kg,iv). After 1 day of operation,rats were killed. Results The infarct size in ischemic preconditioning group decreased significantly than that in ischemic preconditioning plus protein kinase C inhibitor group and simple myocardial infarction group (P<0.01). The hypoxia-inducible factor-1α mRNA gene expression increased in ischemic preconditioning group more than that in ischemic preconditioning plus protein kinase C inhibitor group and simple myocardial infarction group. Hypoxia-inducible factor-1α protein expression had the same change. Conclusions Hypoxia-inducible factor-1α play aprotective role in ischemic preconditioning; protein kinase C is the important signal pathway of hypoxia-inducible factor-1α gene expression.