Avoiding cardiopulmonary bypass (CPB) in coronary artery bypass grafting (CAB G) has been known to reduce early mortality and morbidity. Diabetes Mellitus is a significant risk factor for adverse early and late outcomes after CABG. We compared the clinical results of off-pump CABG versus on-pump CABG in diabetes patients. Material and Method: 682 patients (424 off-pump CABG and 258 on-pump CABG) underwent isolated coronary artery bypass grafting between January 2001 and June 2003. Data were collected 242 patient who had diabetes. Among them, 154 patients underwent off-pump CABG and 90 patients underwent on-pump CABG. We analyzed the preoperative risk factors and postoperative results between 2 groups. Result: Two groups did not show statistical differences in age, sex, coronary and operative risk factors. Operative time was significantly shorter in off-pump CABG, however, number of grafts was fewer in off-pump CABG. Postoperative inotropic usage was lower in off-pump CABG. Postoperative CK-MB level was lower in off-pump CABG, and ICU stay and ventilation time was significantly shorter in off-pump CABG. However, there was no statistical difference between 2 groups in operative mortality, reoperation rate, perioperative myocardial infarction, wound infection, renal failure, neurological complications and hospital stay. Conclusion: Off-pump CABG group showed less myocardial damage and early recovery. We concluded that off-pump CABG is the more reasonable technique in diabetes patients although two techniques showed good results. The long-term follow up and prospective study may be warranted.