Abstract: Objective:To examine the whole blood microRNA-1(miR-1) expression in early acute myocardial infarction(AMI) patients.Methods:Twenty-eight patients with AMI were selected,and 26 patients in control group.In different time periods:after the onset of symptoms of myocardial infarction in patients with AMI admission,8 hours,12 hours,24 hours，7 days,14 days(T0,T8,T12,T24，7 d,14 d),the blood samples were collected and the expression level of miR-1 in whole blood was measured by real-time quantitative PCR,the plasma cardiac troponin I expression in AMI different time was detected by enzyme-linked immunosorbent assay.Results:The miR-1 expression level in whole blood of the patients with AMI at T0,T8,T12,T24，7 d period was significantly higher than in control group(P0.01);while there was no statistical difference between the expression level of miR-1 after AMI 14 days between AMI patients and the patients in control group(P0.05).The curve of the receiver operating characteristic(ROC) curve analysis results suggested that the corresponding area under ROC was 0.839,0.831,0.828,0.835,and 0.774 when miR-1 under the ROC curve was at T0,T8,T12,T24 and 7 d(P0.05).Conclusions:miR-1 in whole blood might be as a kind of biomarkers of early diagnosis in AMI.