Background Fractional flow reserve (FFR) is a well-established method for the evaluation of coronary artery stenosis before PCI. However, whether FFR assessment should be routinely used before CABG remains unclear. Our aim was to compare the outcomes of using FFR with that of conventional CAG (coronary angiography) in guiding CABG. Method This systematic review and meta-analysis was performed according to the PRISMA guidelines. Six studies were included, of which four were double-arm (two prospectively randomised) and two single-arm, reporting data on 1931 patients. A meta-analysis was done for double-arm studies, comparing rates of overall death, MACCE, target vessel revascularisation, spontaneous MI and graft patency. The data of all six studies were entered in a pooled analysis for the endpoints of overall death, spontaneous MI and target vessel revascularisation. Results Meta-analysis demonstrated significantly lower death rates in the FFR-guided than the CAG-guided group (p=0.03) and no significant differences in the rates of MACCE, target vessel revascularisation, spontaneous MI and graft patency. In pooled analysis, FFR-guided group was linked with lower rates of overall death and spontaneous MI. Graft occlusion rate was significantly lower after FFR in one retrospective study, however, this difference was lost in meta-analysis (p=0.24). Conclusion In this meta-analysis, FFR-guided CABG was associated with lower overall death rate and was, at least, non-inferior in the endpoints of MACCE, target vessel revascularisation, spontaneous MI and graft patency than CAG-guided CABG. Further randomized trials are needed to define the role of FFR in guiding CABG surgery.