Objective: To investigate the effects of phase II cardiac rehabilitation in 52 patients undergone coronary artery bypass surgery. Methods: Gradual walking tests, cardio-pulmonary capacity tests and lipid profile were administered to patients selected for phase II cardiac rehabilitation before and after the programme. Training was started on 12-channel electrocardiogram controlled running bands 3 times a week for 20 min periods for 12 weeks fitting the programme. Low or intermediate level exercise programme was applied to patients. Cleveland Clinic Chronotropic Assessment exercise protocol was used during rehabilitation. Results: As a result of phase II cardiac rehabilitation administered to 52 patients undergone coronary bypass operation, exercise capacity, oxygen consumption, anaerobic threshold, cardiac output mean values (p£0.001) and mean HDL cholesterol level (p£0.05) were found to increase, whereas body mass index, total cholesterol, LDL cholesterol and triglyceride mean levels reduced (p£0.001) significantly. Conclusion: In patients who have undergone coronary bypass surgery, phase II cardiac rehabilitation is a very useful programme in improvement of life quality and secondary prevention.