Objective To research the correlation between syndrome characteristics and risk factors of acute ischemic stroke. Methods Totally 1 841 cases of acute ischemic stroke were collected in 23 hospitals from March 2005 to October 2006. A Stroke Syndrome Questionnaire was used to investigate the clinical conditions

individual disease history and past medical history of patients with acute ischemic stroke. The patients were divided into the Yang-syndrome group of 757 cases and Yin-syndrome group of 1 084 cases according to syndrome identification. The risk factors such as gender

smoking history

drinking history

irritability

fatty and sweet diet

obesity

history of diabetes

history of hypertension

history of stroke and history of cervical spondylosis were recorded. The correlation between syndrome characteristics and risk factors was analyzed with Logistic regression. Results There were significant differences between groups in 8 risk factors except obesity and history of cervical spondylosis（ P < 0. 05）. The Logistic regression showed that 3 risk factors i. e. gender

irritability and history of hypertension were closely related to the identification of Yang-syndrome（ P < 0. 05） and the odd ratio（ OR） values were greater than 1. Conclusion The common syndrome of acute ischemic stroke is Yang-syndrome and male

irritability and history of hypertension are closely related to the identification of Yang-syndrome.