Background: Diabetes mellitus (DM) is a major risk factor for cardiovascular disease. It affects about 15% of Middle East population. Patients with DM are known to be a high risk group for early morbidity and mortality following coronary artery bypasses grafting (CABG). The purpose of this study was to identify the impact of DM and its related co-morbidities on short-term morbidity and mortality following CABG, and if there any outcome differences between diabetic and nondiabetic patients. Methods: Data were prospectively collected from 354 patients scheduled for CABG in two tertiary centers during a period of 3 months. Mean age was 56±9years, 205 (57.9%) were diabetics. All patients underwent an elective operation. Results: Diabetics were significantly more hypertensive (74.6% vs. 54.4%, p=0.000), had a history of cerebrovascular stroke (CVS) (7.3% vs. 1.3%, p= 0.01) and congestive heart failure (12.7% vs. 5.4%, p= 0.027). They were less smokers (59.5% vs. 79.9%, p= 0.000) but had higher body mass index (30.2 ± 5.6 vs. 28.2 ± 4.9, p= 0.001). Age was comparable and female gender was more in the diabetic group (p= 0.000). Despite that diabetics had a higher Euroscore (2.4 ± 1.5 vs. 2.0 ±1.3, p= 0.002), no significant differences were found as regards post-operative complications. Post-operative acute renal failure, respiratory failure, CVS, acute myocardial infarction, bleeding, unplanned re-operation or sternal wound infection was all comparable for both groups. Hospital mortality was not statistically significant (4.9% vs. 4%, p= 0.799%) for diabetic and non-diabetic group, respectively. Conclusion: Diabetic patients although had higher pre-operative morbidities, they yet had comparable post-operative morbidity and mortality. Diabetes should not be considered as a risk factor in the outcome of patients undergoing CABG.