Abstract: Objective: To investigate the expression of D-dimer (DD) and uric acid (UA) levels in patients after percutaneous coronary intervention (PCI) and their correlation with prognosis. Methods: A total of 265 patients with coronary heart disease after PCI were selected,and followed up for 1 year according to medical advice after discharge.They were divided into the observation group of 75 cases and the control group of 190 cases based on whether there were any in-stent restenosis (ISR) events during the follow-up period.The general clinical data were compared,including pre-PCI DD,UA and other biochemical indicators in two groups,and the risk factors related to postoperative ISR through binary logistic regression analysis were analyzed.ROC curve analysis was used to determine the area under the curve and the optimal cutoff value of DD and UA levels to predict the ISR of patients after PCI. Results: There was a statistically significant difference in age between the two groups of patients (P<0.01),while there was no statistically significant difference in gender,past medical history,smoking history and drinking history (P>0.05).The pre-PCI DD and UA levels in the observation group were higher than those in the control group,with statistically significant differences (P<0.01).The differences between other biochemical indicators were not statistically significant (P>0.05).The area under the ROC curve predicted by DD and UA for ISR events was 0.820 (95%CI:0.759-0.880) and 0.930 (95%CI:0.899-0.961),respectively.The combined prediction of the two resulted in an area under the ROC curve of 0.966 (95%CI:0.945-0.987).The optimal cutoff value for predicting ISR with DD was 855.0 μg/L (sensitivity 73.3%,specificity 77.9%),the optimal cutoff value for UA was 409.65 μmol/L (sensitivity 88.0%,specificity 83.2%). Conclusions: DD and UA are the independent risk factors for the occurrence of ISR in patients after PCI.Both alone or in combination can be used as auxiliary means to predict the prognosis of patients after PCI.Patients with pre-PCI DD ≥855.0 μg/L,UA ≥409.65 μmol/L are more likely to develop the restenosis.So clinical attention should be paid to such patients and effective preventive measures should be taken as soon as possible for high-risk patients.