The correlation between diabetes and aortic dissection is not fully understood yet, although in literature many studies have suggested that there may be an association between the two conditions. The purpose of this study is to evaluate whether diabetes represents a short- and long-term risk factor for mortality from type A acute aortic dissection. A total of 340 patients with the diagnosis of type A acute aortic dissection underwent aortic surgery between January 2002 and March 2023. The sample was divided into 2 cohorts according to the presence of diabetes (n = 34) or not (n = 306). The mean age was 66 (±12.4) years and 60.9% were male. The primary endpoint was 30-day mortality. Hospital mortality was 12 (35.3%) for the diabetes group and 70 (22.9%) for nondiabetes group (P = 0.098). Overall survival at 10 years was 48.3% [95% confidence interval (CI): 41.6-54.7%], while the 10-year survival for people with diabetes was 29.5% (95% CI: 13.2-47.9%) and for nondiabetes group 50.6% (95% CI: 43.4-57.3%) (Log-rank, P = 0.024). Diabetes was not found to be a risk factor associated with 30-day mortality in patients undergoing surgery for type A acute aortic dissection. It was a risk factor for long-term survival, but this may be related to diabetes complications.