Objective To evaluate the clinic outcomes of coronary artery bypass grafting （CABG） on patients of coronary artery disease complicated with chronic obstructive pulmonary disease（COPD）. Methods The data of 27 patients of coronary artery diseases complicated with COPD who had received CABG from Jan. 1998 to Dec. 2004, were retrospectively summarized. 18 patients received off-pump CABG （off-pump group）,and 9 cases received on- pump CABG （on-pump group）. All patients accepted the evaluation about clinical respiratory complications, oxygenation index （PaO2/FiO2）, related respiratory function index, plasma intercellular adhesion molecule 1 （ICAM-1） and the amount of neutrophil in pulmono-alveolar perfusion fluid at the different time point including the start of CPB （for off-pump group, the measurement accepted at the start of operation）, end of CPB （end of operation for off-pump group）, and at 2, 6, 12, and 24h after operation. Results There was no operation-related death in two groups. One died of respiratory failure 14 days after operation in the hospital in off-pump group, there were more respiratory complications in on-pump group than that in off-pump group, and PaO2/FiO2 in on-pump group was higher than that in off-pump group at CPB 30min （at the start of operation）, but lower than that in off-pump group postoperative at 6 h, 12 h（P〈0. 05）, the concentration of plasma ICAM-1 had obvious difference between two groups from CPB 30 min （at the start of operation） to post-operative 24 h （P 〈 0. 05）. The neutrophils in bronchoalveolar lavage in on-pump group was higher than that in off-pump group from CPB 30 min （at the start of operation） to 24 h after operation （P〈0. 05）. Conclusion Off-pump CABG seems more suitable than on-pump CABG for coronary artery disease patients with COPD due to less damage on oxygen-exchange capability and less respiratory complication.