Objective: To investigate the clinical value of serum small dense low-density lipoprotein cholesterol (sdLDL-C) and homocysteine (Hcy) in the diagnosis of ischemic stroke. Methods: A total of 128 patients with ischemic stroke and 128 healthy subjects (n=128) admitted to Binzhou Central Hospital from June 2021 to July 2022 were enrolled. The serum levels of sdLDL-C, Hcy, HDL-C, LDL-C and lipoprotein Lp(a) were detected by Mindray automatic biochemical analyzer BS2000M2, and the correlation between each index and the clinical characteristics of ischemic stroke was discussed. Results: There were significant differences in the prevalence rates of basic diseases such as hypertension (64.84% vs. 42.97%), hyperlipidemia (60.16% vs. 35.93%) and drinking history (61.72% vs. 38.28%) between the observation group and the control group (P＜0.05), but no statistical differences were observed in diabetes history or smoking history between the two groups (P＞0.05). The detection of biochemical indexes showed that the concentrations of serum LDL-C (3.91±1.62)mmol/L, Lp(a) (368.07±32.04)mg/L, sdLDL-C (4.32±0.59)mmol/L and Hcy (19.71±1.09)μmol/L in the observation group were significantly increased (P＜0.01), while HDL-C (1.16±0.24)mmol/L was significantly decreased (P＜0.05). Pearson correlation analysis showed that serum sdLDL-C and Hcy levels were significantly positively correlated with the severity of ischemic stroke, infarct size and hypertension (P＜0.05), while HDL-C, LDL-C and Lp(a) were not significantly correlated (P＞0.05). The serum concentrations of sdLDL-C and Hcy in severe patients were significantly higher than those in moderate and mild patients (P＜0.05), and showed an upward trend with the aggravation of the disease. Conclusion: Serum sdLDL-C and Hcy concentrations are closely related to the progression of ischemic stroke, and can be used as important diagnostic indicators for disease diagnosis and disease assessment.