Abstract: The aim of the present study was to compare changes in health related-quality of life (H-RQOL) on physical functioning and mental health domains, changes in functional capacity before and 18 months after CABG surgery. Comprehensive data on 187 patients who underwent CABG surgery were prospectively collected, including preoperative factors and postoperative morbidity. Assessing functional status, the change in physical functioning score and change in mental health score were obtained using the physical functioning and mental health subscales out of the eight total subscales of the (SF-36) questionnaire. Also, functional capacity was estimated according to New York Heart Association (NYHA) class. The results showed 18 months after CABG surgery survival rates were (95.7%). Significant improvements in functional status were seen in physical functioning (p<0.001), mental health (p<0.000). However, there were no significant changes in the mean of functional status scores among patients in three age groups. Other significant improvement was found in functional capacity and NYHA class before and the 18 months after CABG. Functional status markedly and significantly improved after CABG surgery, particularly in physical functioning. However, the functional status among survivors of CABG surgery is worse than that of the general population. It seems further research is needed to identify factors explaining the change in H-RQOL to develop interventions to support patients.