We investigated the effects of stent generation on 2-year clinical outcomes between prediabetes and diabetes patients after acute myocardial infarction (AMI). A total of 13,895 AMI patients were classified into normoglycemia (group A: 3673), prediabetes (group B: 5205), and diabetes (group C: 5017). Thereafter, all three groups were further divided into first-generation (1G)-drug-eluting stent (DES) and second-generation (2G)-DES groups. Patient-oriented composite outcomes (POCOs) defined as all-cause death, recurrent myocardial infarction (Re-MI), and any repeat revascularization were the primary outcome. Stent thrombosis (ST) was the secondary outcome. In both prediabetes and diabetes groups, the cumulative incidences of POCOs, any repeat revascularization, and ST were higher in the 1G-DES than that in the 2G-DES. In the diabetes group, all-cause death and cardiac death rates were higher in the 1G-DES than that in the 2G-DES. In both stent generations, the cumulative incidence of POCOs was similar between the prediabetes and diabetes groups. However, in the 2G-DES group, the cumulative incidences of Re-MI and all-cause death or MI were significantly higher in the diabetes group than that in the prediabetes group. To conclude, 2G-DES was more effective than 1G-DES in reducing the primary and secondary outcomes for both prediabetes and diabetes groups.