Background/Aims: Achieving rapid reduction of low-density lipoprotein cholesterol (LDL-C) levels below 55 mg/dL in patients with acute myocardial infarction (AMI) can be challenging with statins alone. This single-center, retrospective study aimed to assess the impact of single-dose injection of evolocumab 140 mg on LDL-C levels during the peri-percutaneous coronary intervention (PCI) period in patients with AMI. Methods: A total of 95 patients with AMI who underwent PCI were divided into the evolocumab (n = 50) and non-evolocumab (n = 45) groups. Results: The percentage change of LDL-C level at 1–3 weeks from baseline was 78.4 ± 13.4% reduction in the evolocumab group versus 45.6 ± 22.6% in the non-evolocumab group, with a mean difference of-33.5% between the groups (95% CI:-42.6 to-24.5%; p < 0.001). The achievement rate of LDL-C levels below 55 mg/dL at 1–3 weeks was significantly higher in the evolocumab group than in the non-evolocumab group (97.7% vs. 60.0%, p < 0.001). Conclusions: Patients with AMI who received single-dose injection of evolocumab 140 mg during the peri-PCI period had a significantly greater LDL-C reduction and higher proportion of patients achieved the target LDL-C level in the early phase AMI than those who did not receive evolocumab.