To observe the prevalence of hyperhomocysteinemia(HHcy) among high risk population of stroke and analyze its risk factors and relevance with the results of carotid artery ultrasound. Methods:The method of crosssectional epidemiologic study was adopted to divide the 5999 patients recruited into two groups: patients with HHcy and patients without HHcy. To compare the differences between the two groups in the aspects of demographic data, risk factors, biochemical assay, and the results of carotid artery ultrasound. Results:The prevalence of stroke and hypertension is higher among patients with HHcy than people without. The prevalence of TIA, dyslipidemia, diabetes is higher among people without HHcy than people with(P<0.01). Multiplefactor analysis shows that age, BMI, HDL, smoking and drinking are the risk factors of HHcy. The proportion of carotid atherosclerotic plaques and multiple carotid atherosclerotic plaques are higher in patients with HHcy than patients without.The proportion of single plaque or no plaque is lower in group without HHcy. The proportion of syndrome factors of endogenous fire and phlegmdampness is higher in the group of HHcy than the other group. The proportion of syndrome factors of endogenous wind is lower in the group of HHcy than the other. Conclusion:HHcy is correlated with stroke, hypertension and carotid atherosclerotic plaques. Besides, age, BMI, HDL, smoking and drinking histories are the risk factors of HHcy.