Angiotensin I-converting enzyme (ACE) gene deletion polymorphism (D) has recently been suggested as a significant risk factor for cerebrovascular disease in studies involving Japanese and white populations. We investigated the role of ACE D polymorphism in the pathogenesis of cerebrovascular disease in Taiwanese.To examine the association of ACE genotype and allele frequency with cerebrovascular disease, we conducted a study of 306 stroke patients and 300 control subjects matched by age and sex.Although the frequencies of both the homozygous deletion (DD) genotype and the D allele were greater in stroke patients than in control subjects, these differences were not significant. Further comparison of the frequencies of the DD genotype and the D allele in the three stroke subgroups (intracerebral hemorrhage, probable large-vessel disease, and probable small-vessel lacunar infarction) with the control group revealed no significant associations. Moreover, ACE gene polymorphism was not significantly associated with age of onset of stroke. Stepwise logistic regression analysis of the presence of the D allele and data on risk factors confirmed the lack of significant association between ACE deletion polymorphism and cerebrovascular disease. Moreover, no association was identified between ACE genotypes and any of the relative risk factors for cerebral infarction or severity of carotid atherosclerosis.Our results suggest that deletion polymorphism of the ACE gene is not associated with the pathogenesis of cerebrovascular disease in Taiwanese.