Abstract: Acute myocardial infarction (AMI) is caused by longterm development of atherosclerosis. Rupture of transluminal coronary atherosclerosis plaques causes local thrombosis and vascular blockage, resulting in AMI. The main clinical symptom is chest pain and patients who do not have timely treatment will die. As an important lethal factor, AMI causes enormous economic and social burden worldwide. MicroRNAs, ~22nt long, inhibit the transcription of mRNA or degrade the targeted mRNA though binding to the 3’UTR of mRNA. These play important roles in many human pathophysiological processes. Recent research results show that microRNAs have great potential in the diagnosis and treatment of AMI.