Objective:To explore the relationship betwwen the different types of ischemic cerebrovascular disease andthe levels of plasma Homocystine(Hcy).Methods:The levels of plasma Hcy in 135 patients with ischemic cerebrovascular disease were measured by the fluorometric method.All the patients were divided into transient ischemic attack(TLA)group and atherothrombotic cerebral infarction(ACO group.The patients in both groups and the levels of plasma Hcy between the primary ACI and recurrent ACI were compared.Results:The levels of plasma Hcy in the ACI group(22.0±6.4 μmol/L)group were significantly higher than those in the TIA group(16.6±6.0 μmol/L)(P＜0.01),and the levels of plasma Hcy in the recurrent ACI group(23.0±5.5 5 μmol/L)were significantly higher than those in the primary group(19.6±5.9 μmol/L)(P＜0.01).There were rio significant differences between the two groups in age,sex,history of smoking.lipid,body mass index,as well as the prevalences of hypertension,diabetes mellitus and coronary heart disease.Conclusions:The increased level of plasma Hcy is closely associated with ACI.and it is a risk factor for recurrent stroke.