Aim To study the relationship between white blood cell count and clinical classification in patients with coronary heart disease and its clinical significance. Methods A total of 301 patients diagnosed with coronary heart disease in the Second Affiliated Hospital of Harbin Medical University from January 2022 to December 2023 were selected as the research subjects, and divided into stable angina pectoris (SAP) group and acute coronary syndrome (ACS) group based on their clinical manifestations and results of electrocardiogram, the differences of general data, biochemical indexes and cardiovascular indexes between the two groups were compared. Spearman correlation analysis was used to analyze the relationship between white blood cell count, neutrophil count and cardiovascular related indicators, including troponin I, N-terminal pro-brain natriuretic peptide (NT-proBNP), ejection fraction, left ventricular end-diastolic diameter (LVEDD), left atrial diameter, Gensini score, etc. ROC curve was employed to determine the cut-off point for diagnosing ACS and SAP classification of coronary heart disease based on white blood cell count, and dividing patients into a group with normal white blood cell level and a group with above normal white blood cell level based on this cut-off point, the differences between the two groups were compared. Results The ratio of hyperlipidaemia history, white blood cell count, neutrophil count, C-reactive protein, platelet count, total cholesterol (TC), low density lipoprotein cholesterol (LDLC), troponin I, NT-proBNP and Gensini score in the ACS group were significantly higher than those in the SAP group (all P＜0.05), while the ratio of aspirin use, the ratio of statin use, and ejection fraction in the ACS group were lower than those in the SAP group (all P＜0.05). Spearman correlation analysis results showed that white blood cell count was positively correlated with C-reactive protein (r＝0.443, P＜0.001), troponin I (r＝0.333, P＜0.001), NT-proBNP (r＝0.245, P＜0.001) and Gensini score (r＝0.341, P＜0.001), but negatively correlated with LVEDD (r＝－0.212, P＜0.001). Similarly, neutrophil count was positively correlated with C-reactive protein (r＝0.430, P＜0.001), troponin I (r＝0.325, P＜0.001), NT-proBNP (r＝0.292, P＜0.001) and Gensini score (r＝0.353, P＜0.001), but negatively correlated with LVEDD ( r＝－0.175, P＝0.002). The cut-off point of white blood cell count in the diagnosis of ACS was 9.35×10⁹ L－1 (sensitivity was 56.7%, specificity was 93.1% ). The patients were divided into normal white blood cell level group (n＝202) and above normal white blood cell level group (n＝99). Hyperlipidemia, smoking history, TC, LDLC, C-reactive protein, troponin I, NT-proBNP and Gensini scores in above normal white blood cell level group were significantly higher than those in the normal white blood cell level group (all P＜0.05), while LVEDD was lower than that in the normal white blood cell level group (all P＜0.05). Conclusion White blood cell count can easily identify the high-risk type of coronary heart disease, and the cut-off point for the diagnosis of ACS is 9.35×10⁹ L－1.