Evidence is limited regarding the impact of healthy lifestyle practices on the risk of subsequent cardiovascular events among patients with diabetes. The purpose of this study was to examine the associations of an overall healthy lifestyle, defined by eating a high-quality diet (top two-fifths of Alternative Healthy Eating Index), nonsmoking, engaging in moderate- to vigorous-intensity physical activity (≥150 min/week), and drinking alcohol in moderation (5 to 15 g/day for women and 5 to 30 g/day for men), with the risk of developing cardiovascular disease (CVD) and CVD mortality among adults with type 2 diabetes (T2D). This prospective analysis included 11,527 participants with T2D diagnosed during follow-up (8,970 women from the Nurses’ Health Study and 2,557 men from the Health Professionals Follow-Up Study), who were free of CVD and cancer at the time of diabetes diagnosis. Diet and lifestyle factors before and after T2D diagnosis were repeatedly assessed every 2 to 4 years. There were 2,311 incident CVD cases and 858 CVD deaths during an average of 13.3 years of follow-up. After multivariate adjustment of covariates, the low-risk lifestyle factors after diabetes diagnosis were each associated with a lower risk of CVD incidence and CVD mortality. The multivariate-adjusted hazard ratios for participants with 3 or more low-risk lifestyle factors compared with 0 were 0.48 (95% confidence interval CI: 0.40 to 0.59) for total CVD incidence, 0.53 (95% CI: 0.42 to 0.66) for incidence of coronary heart disease, 0.33 (95% CI: 0.21 to 0.51) for stroke incidence, and 0.32 (95% CI: 0.22 to 0.47) for CVD mortality (all p trend <0.001). The population-attributable risk for poor adherence to the overall healthy lifestyle (<3 low-risk factors) was 40.9% (95% CI: 28.5% to 52.0%) for CVD mortality. In addition, greater improvements in healthy lifestyle factors from pre-diabetes to post-diabetes diagnosis were also significantly associated with a lower risk of CVD incidence and CVD mortality. For each number increment in low-risk lifestyle factors there was a 14% lower risk of incident total CVD, a 12% lower risk of coronary heart disease, a 21% lower risk of stroke, and a 27% lower risk of CVD mortality (all p < 0.001). Similar results were observed when analyses were stratified by diabetes duration, sex/cohort, body mass index at diabetes diagnosis, smoking status, and lifestyle factors before diabetes diagnosis. Greater adherence to an overall healthy lifestyle is associated with a substantially lower risk of CVD incidence and CVD mortality among adults with T2D. These findings further support the tremendous benefits of adopting a healthy lifestyle in reducing the subsequent burden of cardiovascular complications in patients with T2D. Display omitted