OBJECTIVE To evaluate the impact of comorbid depressive symptoms and/or stress on adverse cardiovascular (CV) outcomes in individuals with diabetes compared with those without diabetes. RESEARCH DESIGN AND METHODS Investigators examined the relationship between baseline depressive symptoms and/or stress in adults with and without diabetes and physician-adjudicated incident CV outcomes including stroke, myocardial infarction/acute coronary heart disease, and CV death over a median follow-up of 5.95 years in the national REGARDS cohort study. RESULTS Subjects included 22,003 adults (4,090 with diabetes) (mean age 64 years, 58% female, 42% black, and 56% living in the southeastern "Stroke Belt"). Elevated stress and/or depressive symptoms were more common in subjects with diabetes (36.8% vs. 29.5%; P < 0.001). In fully adjusted models, reporting either elevated stress or depressive symptoms was associated with a significantly increased incidence of stroke (HR 1.57 [95% CI 1.05, 2.33] vs. 1.01 [0.79, 1.30]) and CV death (1.53 [1.08, 2.17] vs. 1.12 [0.90, 1.38]) in subjects with diabetes but not in those without diabetes. The combination of both elevated stress and depressive symptoms in subjects with diabetes was associated with a higher incidence of CV death (2.15 [1.33, 3.47]) than either behavioral comorbidity alone (1.53 [1.08, 2.17]) and higher than in those with both elevated stress and depressive symptoms but without diabetes (1.27 [0.86, 1.88]). CONCLUSIONS Comorbid stress and/or depressive symptoms are common in individuals with diabetes and together are associated with progressively increased risks for adverse CV outcomes.