Abstract：Objective：To investigate the predictive values of phlegm-damp syndrome scores combined with left ventricular ejection fraction（LVEF）for in-stent restenosis（ISR）after percutaneous coronary intervention（PCI）in patients with coronary heart disease．Methods：Patients with coronary heart disease who underwent PCI were enrolled and divided into the ISR group and the non-ISR group based on ISR occurrence． All patients underwent echocardiography and were assessed for syndrome scores according to the diagnostic criteria for phlegm-damp syndrome in coronary heart disease．General information，laboratory indices，phlegm-damp syndrome scores，and LVEF were compared between the two groups． Logistic regression was used to analyze the risk factors of ISR after PCI， while receiver operating characteristic（ROC）curves were used to evaluate the diagnostic efficacy of phlegm-damp syndrome scores，LVEF，and their combination for ISR．Results：It was suggested that significant differences existed between ISR and non-ISR groups in low-density lipoprotein cholesterol（LDL-C），LVEF，and phlegm-damp syndrome scores （P＜0.05）． Logistic regression revealed reduced LVEF as a risk factor for ISR（OR=4.424， P=0.002）， while a phlegm-damp syndrome score≥ 6 was an independent risk factor（OR=12.875，P=0.003）．ROC analysis showed that the area under the curve for predicting ISR was 0.834 using the phlegm-damp syndrome scores alone and 0.847 when combined with LVEF．Conclusion：The combination of phlegm-damp syndrome scores and LVEF demonstrates high predictive value for ISR after PCI． This integrated approach may serve as a key clinical indicator for ISR risk assessment，providing a reference for early clinical intervention.