Aim To investigate the relationship between systemic inflammatory immune index (SII) and systemic inflammatory response index (SIRI) and the risk of in-hospital major adverse cardiovascular events (MACE) in patients with acute myocardial infarction (AMI). Methods Retrospective analysis was conducted on AMI patients admitted to the Second Cardiovascular Disease Area of Suining Central Hospital from February 2021 to May 2022. Based on inclusion and exclusion criteria, 246 patients were finally enrolled. According to whether MACE occurred during hospitalization, they were divided into event group and non-event group, and baseline data of the two groups were compared.All variables except SII and SIRI were included in a univariate-multivariate Logistic regression analysis to screen factors affecting the risk of MACE, and were used as significant covariates for adjustment to evaluate the relationship between SII and SIRI and the risk of MACE respectively. Results The results of multivariate Logistic regression analysis showed that emergency PCI, left ventricular ejection fraction, albumin level and age were significant factors affecting the risk of in-hospital MACE in AMI patients (OR＝0.2,5%CI:0.194～0.960, P＝0.038; OR＝0.0,5%CI:0.890～0.969, P＝0.001; OR＝0.0,5%CI:0.621～0.845, P＜0.001; OR＝1.3,5%CI:1.070～1.228, P＜0.001), and a basic model was established based on this. After adjusting for the significant covariates, SII and SIRI were both independent risk factors for in-hospital MACE (OR＝1.4,5%CI:1.001～1.008, P＝0.002; OR＝4.7,5%CI:2.597～8.142, P＜0.001). The areas under the curves of SII and SIRI were 0.658 and 0.785, respectively, and the optimal cutoff values were 434.83 and 1.03. Restricted cubic spline analysis showed that SII (Nonlinear P＝0.639) and SIRI (Nonlinear P＝0.683) were linearly related to the risk of MACE after adjusting significant covariates. Threshold effect analysis showed that when SIRI＞0.93, the risk of MACE began to increase. Conclusion Elevated levels of SII and SIRI are independent risk predictors for the occurrence of in-hospital MACE in AMI patients.