Aim To explore the predictive value of fractional flow reserve (FFR) immediately after percutaneous coronary intervention (PCI) on the prognosis of patients. Methods This study included patients (200 cases) who underwent PCI treatment in our hospital from March 2014 to December 2017. A 1-year follow-up (re-examination by telephone and outpatient) was carried out after the operation, and the patients were divided into MACE group and non-MACE group according to whether there were major adverse cardiovascular events (MACE) during the follow-up period. Perform univariate and multiple Logistic regression analysis to analyze the influencing factors of MACE after PCI, establish receiver operating characteristic curve (ROC curve) to analyze the predictive value of FFR and draw Kaplan-Meier curve to verifyit, and analyze the influencing factors of postoperative FFR. Results After 1 year of follow-up, 31 cases were in the MACE group and 169 cases were in the non-MACE group. The postoperative FFR of MACE group was significantly lower than that of non-MACE group [t＝6.316, P＝0.000]. The proportion of patients with diabetes, hypertension and hyperlipidemia in MACE group was significantly higher than that of non-MACE group (P＜0.05). Multivariate analysis showed that hypertension, diabetes, hyperlipidemia, and postoperative FFR were the influencing factors of MACE. ROC curve showed that postoperative FFR had a better predictive value for MACE (P＝0.000), and postoperative FFR＝0.868 was the best critical value. Survival analysis showed that the incidence of MACE in the postoperative FFR≥0.868 group was later than that in the postoperative FFR＜0.868 group (Log-rank P＝0.008); multivariate analysis showed that postoperative FFR influencing factors included right coronary target vessel involvement and preoperative FFR value and stent diameter (P＝0.2,0.4,0.038, all P＜0.05). Conclusions Postoperative FFR has a good predictive value for the prognosis of PCI. The incidence of MACE in the postoperative FFR≥0.868 group is later than that in the postoperative FFR＜0.868 group. Involvement of the right coronary target vessel, preoperative FFR value and stent diameter are the influencing factors of postoperative FFR.