Objective To analyze the relationship between white blood cell count to mean platelet volume ratio (WMR), red cell distribution width (RDW), and neutrophil to lymphocyte ratio (NLR) levels and major adverse cardiovascular events (MACE) after percutaneous coronary intervention (PCI) in acute myocardial infarction (AMI) patients.Methods A total of 262 AMI patients who were admitted to our hospital from January 2018 to December 2019 and treated with PCI were enrolled. According to whether MACE occurred within 30 days after operation, they were divided into MACE group and non-MACE group. The medical records of these patients were collected, and the automatic blood cell analyzer was applied for blood routine examination to measure RDW and to calculate WMR and NLR. Preoperative WMR, RDW, and NLR levels were compared between the two groups. Receiver operating characteristic (ROC) curve was plotted to analyze the efficacy of WMR, RDW and NLR in predicting MACE in AMI patients after PCI. Multivariate Logistic regression analysis was performed to determine the independent risk factors for MACE after PCI.Results The preoperative levels of WMR, RDW, and NLR in the MACE group were higher than those in the non-MACE group (P < 0.05). The optimal cut-off value of WMR for predicting MACE after PCI was 1,404.25×10^-6/L², where the area under the ROC curve (AUC) was 0.916, the specificity was 88.69% (95% CI: 0.832, 0.927), and the sensitivity was 91.11% (95% CI: 0.871, 0.943 ). The optimal cut-off value of RDW for predicting MACE after PCI was 13.81%, where the AUC was 0.808, the specificity was 83.93% (95% CI: 0.782, 0.883), and the sensitivity was 82.22% (95% CI: 0.776, 0.875). In addition, the optimal cut-off value of NLR for predicting the MACE after PCI was 5.66, where the AUC was 0.832, the specificity was 91.71% (95% CI: 0.886, 0.944), and the sensitivity was 86.67% (95% CI: 0.822, 0.904). Multivariate Logistic regression analysis showed that WMR [O^R = 2.818 (95% CI: 1.493, 5.318)], RDW [O^R = 1.613 (95% CI: 1.098, 2.368)], and NLR [O^R = 2.643 (95% CI: 1.344, 5.198)] were risk factors for MACE after PCI in AMI patients (P < 0.05).Conclusions High levels of preoperative WMR, RDW and NLR are risk factors and of predictive value for MACE after PCI in AMI patients.