Objective:The purpose of this single center study was to investigate the characteristics of predisposing factors,location of infarction selection of treatment and etc. in patients younger than 40 years with acute myocardial infarction(AMI). Methods:We collected and analyzed the clinical data of 218 patients with AMI from January 1999 to January 2009. All characteristics were compared between young (≤40 yrs) and elder patients(60~75 yrs). Results:There were 106 cases in the young group and 112 cases in the elder group. There were 46.23% patients in the young group without a clear etiology,and drinking was one of the distinctive predisposing factors for young patients. For the young group,AMI was localized in 54.64% anterior wall,followed by 48.45% inferior and posterior wall;however,for the elder group,AMI was localized mainly in 58.33% inferior and posterior wall. Compared with the elder group,the left ventricular end-systolic diameter in the young group was smaller (P < 0.01),while with no significant difference in left ventricular ejection fraction. Young patients were more likely to be treated with thrombolytic therapy,thrombolytic therapy plus selective stent implantation than the elder patients. Conclusion:Young people should pay attention to physical examination and improve the lifestyle. Young patients are more likely to have AMI in the anterior wall. Although clinical treatment is positive,it is still has a big disparity compared with the guidelines recommendation. Hospitals should speed up the establishment of green channel to benefit more partients.