Atherosclerotic cardiovascular disease (ASCVD) is a disease caused by the accumulation of atherosclerotic plaques that leads to arterial hardening and impairment of contractility. Proprotein convertase subtilisin/kexin type 9 (PCSK9) can increase low-density lipoprotein cholesterol levels in plasma, which accelerates the development and progression of ASCVD. This article intends to review the biological characteristics and functional mechanisms of PCSK9, elucidate its impact on the development and progression of ASCVD, provide research literature support for the diagnosis and treatment of such diseases and improving the prognosis of patients.