Objective To construct and validate a predictive model for the risk of major adverse cardiovascular events (MACEs) in patients with ST-segment elevation myocardial infarction (STEMI) within 2 years after primary PCI. Methods This was a retrospective cohort study in which 554 study subjects were randomized in a 3〖DK〗∶1 ratio into a modelling cohort and a validation cohort. Multifactorial Cox regression was applied to analyze independent risk factors for the 2-year risk of MACEs events in patients with STEMI after primary PCI. R software (version 3.5.3) was used to construct a nomogram model to predict the 2-year risk of MACEs in STEMI patients after primary PCI, and the model was compared and validated. Results Results of multifactorial Cox regression analysis showed that age, male, Killip classification, plasma DPP4 activity, diabetes mellitus, and smoking history were independent risk factors for the development of MACEs in STEMI patients at 2 years after primary PCI. The prediction model was validated internally and externally with an AUC value of 0.853 (95% CI: 0.832-0.874) in the modelling cohort and 0.831 (95% CI: 0.803-0.859) in the validation cohort. The results of the Hosmer-Lemeshow test suggest that the model has good stability in predicting outcomes. Conclusion The nomogram model proposed in this study can effectively predict the 2-year mace risk of STEMI patients after primary PCI.