As a key regulator of cholesterol homeostasis, the pre protein converting enzyme Bacillus subtilisin/kexin type 9 (PCSK9) can induce the degradation of LDL receptors (LDLR) to regulate circulating low-density lipoprotein cholesterol (LDL-C) levels. Inhibiting the action of PCSK9 can reduce the risk of type I myocardial infarction in individuals with normal blood lipids. The root cause of type I myocardial infarction is myocardial necrosis caused by spontaneous coronary atherosclerotic thrombosis, and in this process, the role of PCSK9 in regulating blood lipids has gone beyond the original scope. Clinically, exploring this area may enhance physicians' understanding of the role of PCSK9 in type I myocardial infarction and provide new ideas for secondary prevention and treatment of type I myocardial infarction.