OBJECTIVE To investigate the effects of evolocumab combined with atorvastatin on post-percutaneous coronary intervention （PCI） efficacy and coronary microcirculation in patients with acute ST-segment elevation myocardial infarction （STEMI）. METHODS This retrospective cohort study included 194 hospitalized patients with acute STEMI who underwent PCI in the First Affiliated Hospital of Nanyang Medical College from Jan. 2022 to Dec. 2024. The patients were divided into control group （100 cases） and combination therapy group （94 cases） according to the different therapy plans. The control group was given Atorvastatin calcium tablets orally， at a dose of 20 mg， once a day. On the basis of the control group， the combination therapy group received an initial injection of Evolocumab injection 140 mg within 24 hours after PCI， followed by subsequent injections every 2 weeks. Both groups received continuous treatment for at least 30 days. Blood lipid indicators [total cholesterol （TC）， triglycerides （TG）， low-density lipoprotein cholesterol （LDL-C） and high-density lipoprotein cholesterol]， inflammation indicators [C-reactive protein （CRP） and interleukin-6 （IL-6）]， vascular Δ 基金项目河南省医学科技攻关计划项目（No.LHGJ20230971） endothelial function and microcirculation indicators [fibrinogen， ankle-brachial index （ABI） and nitric oxide （NO）]， cardiac function indicators [left ventricular ejection （LVEF）， left ventricular end-diastolic diameter and left ventricular end-systolic diameter] before treatment and after 30 days of treatment， as well as the occurrence of adverse reactions during the treatment， were compared between the two groups. RESULTS Before treatment， there were no statistically significant differences in the levels of the indicators of blood lipid， inflammation， vascular endothelial function and microcirculation， and cardiac function between the two groups （P＞0.05）. After 30 days of treatment， the levels of TC， TG， LDL-C， CRP， IL-6 and fibrinogen in both groups were significantly reduced compared to those before treatment within the same group. The levels of NO and LVEF in both groups， as well as ABI in the combination therapy group， were significantly elevated compared to those before treatment within the same group. Moreover， the improvements in the levels of TC， LDL-C， CRP， IL-6， fibrinogen and NO in the combination therapy group were more pronounced than those in the control group during the same period （P＜0.05）. There were no statistically significant differences in the incidence of liver function impairment， gastrointestinal adverse reactions， or the overall incidence of adverse reactions between the two groups （P＞0.05）. CONCLUSIONS Compared with atorvastatin alone， evolocumab combined with atorvastatin more effectively reduces the blood lipid levels， improves the inflammatory status， vascular endothelial function and coronary microcirculation in patients with acute STEMI after PCI， while the safety is comparable to that of atorvastatin alone.