Objective Explore the correlation between levels of remnant cholesterol（RC）and the severity of coronary artery stenosis in patients with acute coronary syndromes（ACS），and evaluate the predictive value of RC on the degree of coronary artery stenosis in patients with ACS. Methods A total of 376 ACS patients treated in the department of cardiology of the Affiliated Hospital of Chengde Medical University from April 2019 to March 2020 are divided into two groups，namely，the mild stenosis（Gensini < 36）group and the moderate to severe stenosis group（Gensini ≥ 36）according to the score results of coronary arteriography Gensini. Meanwhile，basic clinical data and blood lipids of the two are compared. Besides，the analyze ⁃ regression ⁃ binary logistic method is used to analyze the correlation between RC levels and coronary artery stenosis severity，while the ROC curve is employed to predict the accuracy of RC on the degree of coronary stenosis in patients with ACS. Results In the single variable analysis of this study，common risk factors for the severity of coronary artery stenosis among ACS patients like men，cigarette smoking，hypertension，and diabetes mellitus，vary significantly between the two groups. Compared with the mild stenosis group，the level difference of TG，non⁃HDL⁃C，RC，LDL⁃C，HDL⁃C， ALB and CRE in the moderate to severe stenosis group（P < 0.05）is statistically significant. Through Analyze⁃ Regression ⁃binary logistic，it is revealed that hypertension，cigarette smoking，diabetes mellitus，HDL⁃C，non ⁃ HDL⁃C，and RC are the independent risk factors for the severity of coronary artery stenosis in ACS patients（P < 0.05）. The ROC curve shows the area under the coronary stenosis severity curve of serum RC prediction in ACS patients of 0.733. Conclusion RC is positively correlated with the degree of coronary artery vascular stenosis in ACS patients，and RC can be an early screening indicator to predict the degree of coronary artery stenosis. RC， which is positively correlated with the degree of coronary artery vascular stenosis in ACS patients，can be turned into an early screening indicator to predict the degree of coronary artery stenosis.