BACKGROUND Multivessel off-pump coronary artery bypass grafting (CABG) has been performed with favorable results in our institute. In this study, we analyzed the outcomes in patients who underwent off-pump CABG for left main disease, since the surgical outcomes for such patients have not been clarified. METHODS Between March 1, 1999 and July 30, 2002, a total of 147 patients with left main disease (112 males and 35 females, mean age 66.9 +/- 9.8 years) underwent off-pump CABG. Perioperative and follow-up data were entered into a structured database and the results were analyzed. RESULTS Urgent or emergent surgery was performed in 25 patients (17.0%), and a preoperative intra-aortic balloon pump was used in 12 patients (8.2%). The mean number of bypass grafts was 3.2 +/- 1.0, and complete revascularization was performed in 127 patients (86.4%). There were 4 incidences of intraoperative conversion from off-pump to on-pump surgery. The mean intubation period, intensive care unit stay and postoperative hospital stay were 9.4 +/- 13.0 h, 2.3 +/- 1.4 days and 13.4 +/- 7.3 days, respectively. There was 1 hospital death (0.7%). Postoperative myocardial infarction was observed in 2 patients (1.4%), postoperative stroke in 1 (0.7%), prolonged ventilator support in 5 (3.4%) and mediastinitis in 3 (2.0%). During the follow-up period of 2.1 +/- 1.0 years, there were 4 deaths and 7 cardiac events. The actuarial 3-year survival rate was 97.0%, and the event-free rate was 94.3%. CONCLUSIONS Our observations support off-pump CABG as a surgical option with a favorable outcome for patients with left main disease.