Background: This study aims to evaluate pre- and postoperative health-promoting lifestyle behaviors among patients undergoing coronary artery bypass graft surgery. Methods: A total of 208 patients (170 males; 38 females; mean age 57.1 +/- 8.5 years; range 32 to 78 years) without communication problems who underwent elective coronary artery bypass graft surgery in Kartal Kosuyolu Yuksek I htisas Training and Research Hospital, were included. Health-promoting lifestyle behaviors were assessed preoperatively and at six weeks following surgery using the Health Promotion Lifestyle Behaviors Scale. Results: The mean scores for Health-Promoting Lifestyle Behaviors of the patients at six weeks following surgery significantly increased than the preoperative scores. There was also a significant increase in the scores for the self-actualization and interpersonal support sub-dimensions of the scale. The scores for the health responsibility, exercise, and stress management sub-dimensions significantly decreased at six weeks following surgery. Conclusion: Coronary artery bypass graft surgery affects health-promoting lifestyle behaviors of the patients. It can be concluded that self-actualization skills of the patients and communication with their immediate family increase, where as their responsibility toward their own health, exercise levels, meal arrangements, and stress management decrease at six weeks following surgery.