Abstract: AIM To investigate factors affecting in-hospital mortality in patients with acute myocardial infarction (AMI). METHODS A retrospective study was conducted in 2 136 patients with AMI, whose baseline characteristics and therapeutic approaches during hospital stay were compared between the survivors (1 968) and the dead (168). To identify the significant factors predictive of in-hospital death, multivariate logistic regression analysis was performed. RESULTS Compared with those of the survivors, the dead were substantially older ［(71±10) vs (62±11) years, P<0.01］, had a higher prevalence of hypertensive disease, diabetes mellitus and hyperlipidemia (58.3% vs 43.2%, 47.7% vs 21.1%, 72.0% vs 58.8%, respectively, all P<0.01), less related to cigarette smoking (45.2% vs 54.2%，P<0.05), but had a higher Killip class of cardiac function on admission (2.0±1.1 vs 1.2±0.5, P<0.01). Compared with those of the survivors, reperfusion therapy within the first 12 hours after symptom onset and the use of beta receptor blockers and nitrates were lower during hospitalization phase in the dead patients (10.1% vs 30.3%，47.0% vs 71.1%，95.2% vs 98.6%, respectively, all P<0.01). The results of logistic regression demonstrated that age, diabetes mellitus, hypertensive disease, Killip classification of cardiac function, reperfusion therapy, and uses of beta receptor blockers and nitrates were significant factors affecting in-hospital death in patients with AMI. CONCLUSION Age, diabetes mellitus, hypertensive disease, Killip classification of cardiac function, reperfusion therapy and uses of beta receptor blockers and nitrates are the significant factors affecting in-hospital death in patients with AMI.