OBJECTIVE： To explore loading dose simvastatin on related indicators in PCI perioperative period of patients with acute myocardial infarction. METHODS： Data of 203 acute myocardial infarction patients undergoing emergency PCI were retrospectively collected and divided into observation  group （102 cases） and control group （101 cases） by different regimens. Control group received conventional treatment for 3 d before PCI， including orally taking Aspirin enteric-coated tablet 300 mg/d， qd + Simvastatin tablet 40 mg/d， qd， simvastatin 40 mg/d after surgery， qd， for 4 weeks. Observation group received Simvastatin tablet 80 mg 2 h before PCI， the other treatment was the same with control group. Total cholesterol （TC）， triglyceride （TG）， low-density lipoprotein cholesterol （LDL-C），high-density lipoprotein cholesterol （HDL-C）， IL-6， IL-10，TFN-α， plasma super-sensitive troponin （TNT-HSST） level， creatine kinase isoenzyme （CKMB） level， high sensitive C-reactive protein （hs-CRP） level and transaminase level before and 24 h after treatment were observed and the incidence of adverse reactions was recorded. Meanwhile， the incidence of postoperative 30 d of MACE and CIN was followed-up. RESULTS： There was no significant difference in TG， TC， LDL-C， HDL-C before and after treatment （P＞0.05）. Before treatment， there was no significant difference in TNF-α， IL-6，IL-10，hs-CRP， CKMB， TNT-HSST levels in 2 groups （P＞0.05）； after treatment， TNF-α， IL-6， hs-CRP， CKMB， TNT-HSST levels were significantly higher than before （P＜0.05）， and TNF-α，IL-6， hs-CRP levels in observation group was significantly lower than control group，CKMB，TNT-HSST levels were significantly higher than control group； IL-10 was significantly lower than before in 2 groups，and observation group was higher than control group， with statistical significance （P＜0.05）. The MACE rate and CIN rate in observation were lower than control group with statistical significance（P＜0.05）. And no obvious adverse reaction was found in 2 groups. CONCLUSIONS： Loading dose simvastatin in PCI perioperative period can significantly reduce patients’ PCI， TNF-α， hs-CRP， CKMB， TNT-HSST levels and the incidence of cardiovascular and renal adverse reactions.