Coronary angiography is an important diagnostic tool for coronary heart disease. While it can identify anatomical coronary stenosis, its ability to identify hemodynamic changes is limited. The Fractional Flow Reserve (FFR) technique, combined with coronary angiography, facilitates both the functional and anatomical assessment of heart disease. New studies have shown that FFR has unique advantages in guiding percutaneous coronary intervention (PCI), and it is currently being used in coronary artery bypass graft (CABG) as well as for assessing the prognosis of patients after surgery. It may also play a significant role in assessing the patency of a graft. However, some studies have shown that in considering the cardioprotective benefits of CABG, applying FFR guidelines to CABG may reduce or impair its "surgical collateralization" effect and increase the rate of incomplete revascularization. We compared the advantages and disadvantages of FFR to guide PCI and CABG, which will provide health practitioners with useful resources to determine the best diagnosis and treatment for patients.