Abstract: Intramyocardial hemorrhage (IMH) is one of the adverse cardiovascular events of acute myocardial infarction, which is due to the persistent ischemia and hypoxia leading to vascular endothelium dysfunction and leakage of red blood cells into musculature. The morbidity of IMH is 41% among acute myocardial infarction patients receiving reperfusion, which seriously affects coronary reperfusion therapy. In recent years, IMH has received widespread attention and studies have shown that IMH is related to microvascular obstruction (MVO). However, early identification and accurate evaluation of IMH need to be further studied. In this article, we summarize the risk factors, mechanisms and evaluation methods of IMH, intending to provide new therapeutic options for clinical treatment.