Among the sick patients suffering from non-ST segment elevation acute coronary syndrome (NSTEACS), the accuracy of fractional flow reserve (FFR)-directed percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) is still ambiguous. Studies were obtained from PubMed, Embase, Wanfang Data, and Cochrane Library electronic statistics from their initiation up to April 2018, to explore the differences between the FFR-directed approach and the coronary angiography (CA)/stress perfusion scintigraphy (SPS)-directed approach in the outcomes of NSTACS patients. Odds ratio was determined for individual studies, quality assessments, heterogeneity, and publishing bias analyses. In total, there were 5 studies involving 1,366 patients (606 FFR patients and 760 CA patients). Compared with CA, the collection of the studies indicated that FFR had a lower incidence of myocardial infarction (MI) (OR, 0.61; 95% CI: 0.39-0.96; p <0.05). However, none showed important disparities in main adverse cardiovascular events (MACE, OR, 0.74; 95% CI: 0.53-1.03; p=0.07), all-cause death rate (OR, 0.83; 95% CI: 0.45-1.54; p = 0.56), and major bleeding (OR, 1.00; 95%CI: 0.25-4.03; p=1). The FFR-directed management of patients with NSTEACS had a close relationship with the serious decrease in incidence of MI without statistical significance. Future large-scale research, which is carried out at random and with a control, is needed to confirm these conclusions.