Abstract: Objective To study the association of serum homocysteine (Hcy) level with stroke in coronary heart disease patients. Methods In this study, 130 patients with coronary heart disease and stroke were included as observation group, and 145 patients with coronary heart disease were included as control group. The serum Hcy level was detected and its association with stroke in coronary heart disease patients was analyzed. Results The diabetes history, hypertension history, smoking history, BMI ≥ 25 kg/m2, years of coronary heart disease, Hcy level and LDL-C level in the observation group were significantly higher than those in the control group (P < 0.05). Multivariate analysis showed that diabetes history, hypertension history, smoking history, increased Hcy and LDL-C levels were the risk factors of cerebral stroke in the patients with coronary heart disease (P < 0.05). The subjects with Hey level in the highest quartile (>15.77 μg/ml) had 84% higher risk to develop stroke compared with those whose Hey level was within the lowest quartile (< 10.33 μg/ml) with significant difference (P = 0.024); even after correction of the related risk factors, the risk rate was 74% higher (P = 0.045). Conclusions Elevated serum Hcy level is the high risk factor of cerebral stroke in patients with coronary heart disease. With the elevation of serum Hcy level, the risk further increases.