Objective To investigate the surgical therapy for chronic total occlusion (CTO) of coronary artery with offpump coronary artery bypass grafting (OPCAB). Methods From Aug. 1999 to Oct. 2007, 696 patients with 853 totally occluded coronary arteries (127 coronary arteries lack of opacification while the other 726 arteries with reverse flow showed by coronary angiography) underwent OPCAB. A total of 2 231 grafts were constructed including 136 placed to coronary endarterectomy (CE) targets and 28 arterialized middle cardiac veins. Blood flow was detected during operation in 26 coronary arteries with no opacification in preoperative angiography, while no blood flow was detected in 63 coronary arteries with opacification in preoperative angiography. Cardiopulmonary bypass was applied in 15 cases because of a poor hemodynamics and 6 of which were assisted with intraaortic balloon pump(IABP). Results All patients survived the operation. 6 died in hospital because of low cardiac output (2 cases), renal failure (2 cases), perioperative cardiac infarction (1 case) or cerebrovascular accident (1 case). Stress ulceration occurred in one case, mediastinal infection occurred in another case after operation. Both were treated medically and recovered. 692 patients were followed up and the rate of flup was 99.42%(685/686)， with 4 withdrawal. Freedom from cardiac angina was 99.85%(685/686) and cardiac functional grading (NYHA) was Ⅰ-Ⅱ. Conclusion OPCAB can be well performed in patients with chronic total occlusion of coronary arteries. The ralue of coronary angiography for evaluating totally occluded coronary artery is limited, and endoscope or intravascular ultrasound techniques may be helpful.