Objective: To investigate the value of serum triglyceride and fasting glycemic index in predicting no reflow in patients with acute myocardial infarction after percutaneous coronary intervention. Methods: A total of 1037 patients with acute myocardial infarction who received PCI in the Department of Cardiology of Shanghai General Hospital and Jiading Branch of Shanghai General Hospital from January 2016 to May 2021 were retrospectively selected. According to postoperative TIMI blood flow classification, all patients were divided into no reflow group (TIMI blood flow≤grade 2) (309 cases) and reflow group (TIMI blood flow = grade 3) (728 cases). Clinical data, laboratory indicators and surgical information were collected from the two groups of patients. Logistic univariate and multivariate regression were used to analyze the independent risk factors of no reflow in actue myocardial infarction patients after PCI. ROC curve was used to analyze the best cut-off point for TyG index to predict the occurrence of no reflow. Results: The TyG index of no reflow group was significantly higher than of reflow group (7.16±0.64 vs 6.63±0.38, P=0.001). Multivariate logistic regression analysis showed that TyG index(OR=1.484,95%Cl 1.203-1.831,P< 0.001);WMSI(OR=2.640,95%Cl1.036-4.722,P=0.039);CSI (OR=2.299,95%Cl1.117-4.767,P=0.022) was independent predictors of no reflow phenomenon in patients with acute myocardial infarction after PCI .The area under the ROC curve predicted by TyG index after PCI without reflow was 0.809,95%Cl(0.740-0.879),higher than CSI and WMSI.When the TyG index was 6.995, the sensitivity and specificity of Youden index were 82.4% and 70.3% respectively at the maximum.Conclusion: TyG index can be used as an indicator to predict the occurrence of no-reflow in patients with acute myocardial infarction after PCI, which is helpful for clinicians to select high-risk patients and take interventions timely, so as to reduce the risk of no-reflow in patients after PCI.