BACKGROUND: The association between type 1 diabetes mellitus (T1DM) and specific cardiovascular diseases (CVD) is uncertain. Furthermore, data on type 2 diabetes mellitus (T2DM) in relation to risk of aortic valve stenosis, atrial fibrillation, abdominal aortic aneurysm, and intracerebral hemorrhage are scarce and inconclusive. We examined the associations of T1DM and T2DM with incidence of seven CVD outcomes. METHODS: This study comprised 71,483 Swedish adults from two population-based prospective cohorts. T1DM and T2DM diagnosis and incident CVD cases were ascertained through linkage with the population-based registers. RESULTS: T1DM was associated with myocardial infarction (hazard ratio [HR] 3.26; 95% confidence interval [CI] 2.47-4.30), heart failure (HR 2.68; 95% CI 1.76-4.09), and ischemic stroke (HR 2.61; 95% CI 1.80-3.79). Increased risk of myocardial infarction, ischemic stroke, and heart failure was also observed in T2DM patients and the magnitude of the associations increased with longer T2DM duration. T2DM was also associated with an increased risk of aortic valve stenosis (HR 1.34; 95% CI 1.05-1.71) and with lower risk of abdominal aortic aneurysm (HR 0.57; 95% CI 0.40-0.82) and intracerebral hemorrhage (HR 0.51; 95% CI 0.30-0.88). Only long-term T2DM (≥20 years) was associated with an increased risk of atrial fibrillation (HR 1.44; 95% CI 1.02-2.04). CONCLUSION: T1DM and T2DM are associated with increased risk of major CVD outcomes. TRIAL REGISTRATION: The Cohort of Swedish Men and the Swedish Mammography Cohort are registered at clinicaltrials.gov as NCT01127711 and NCT01127698, respectively.