Objective To compare the differences in clinical manifestation and treatment measures in very old patients and elderly patients with acute myocardial infarction (AMI). Methods Clinical data of 354 identified AMI patients who were admited in our hospital from June 2008 to June 2012 were subjected in this study. They were divided into 2 groups, that is, very old group [age ranging from 75 to 91years, mean (79.5±3.4)years, n＝46] and elderly group [age ranging from 36 to 74years, mean (61.8±8.4)years, n＝308]. Their clinical symptoms, risk factors and management strategies were retrospectively analyzed, and compared between the 2 groups. Results There were more patients having dyspnea, fatigue and other heart failure symptoms as the first symptoms at AMI onset in very old group than in elderly group (39.1% vs 16.6%，P＜0.01). More women (56.5% vs 29.2%, P＜0.05) and more non-ST-segment elevation myocardial infarction (45.7% vs 28.2%, P＜0.01) was found in very old group (P＜0.01). In very old group, there were more patients with hypertension (60.9% vs 47.1%, P＜0.05) and with diabetes mellitus (34.8% vs 15.6%, P＜0.05), but less patients with dyslipidemia (32.6% vs 52.3%, P＜0.05) and cigarette smoking (34.8% vs 63.6%, P＜0.05) when compared with those from elderly group. Time from symptom onset to hospital admission was significantly longer in very old group (P＜0.05). Both coronary angiography (78.2% vs 95.8%, P＜0.05) and reperfusion procedures (71.8% vs 94.8%, P＜0.05) were less applied to the very old patients (P＜0.05). Worsening renal function was more frequently in very old patients(6.5% vs 0.3%, P＜0.05). Conclusion There are more atypical clinical presentation and less reperfusion therapy in very old patients with acute myocardial infarction.