Although type A behavior (TAB) has been shown to be related to coronary heart disease, the relationship between TAB and stroke was rarely investigated. We studied TAB in stroke patients with the use of the questionnaire developed by Eysenck and Fulker that has 4 subdimensions: Tenseness, Ambition, Activity, and Unrepressed. The questionnaire was administered to 224 patients with acute stroke and 100 controls. The patients were further classified as having cerebral infarction (large vessel infarction and small vessel infarction), and intracerebral hemorrhage. We found that, among the 4 subdimensions, only the Tenseness score was significantly higher in patients with cerebral infarction but not in those with intracerebral hemorrhage compared to the controls. On subgroup analysis, Tenseness score was higher in patients with large vessel infarction but not in those with small vessel infarction than in those with intracerebral hemorrhage or controls. The association of high Tenseness score with cerebral infarction (and large vessel infarction) remained significant after multiple logistic analysis adjusting various risk factors such as hypertension, diabetes mellitus, cigarette smoking and habitual alcohol drinking. Our data suggest that a high Tenseness dimension of TAB may be an independent risk factor for ischemic stroke, probably associated with atherogenesis.