The angiotensin-converting enzyme (ACE) is a rate-limiting enzyme in the renin angiotensin system, the enzyme is involved in the vascular remodelling and atherosclerosis. Its significance in pathogenesis of ischemic cerebrovascular insults (CVI) is not known. We analysed 124 Slovenian patients with CVI and compared them with 161 healthy controls for I/D polymorphism. Under a recessive model (chi2 = 1.76, p = 0.1, OR = 1.40, 95% CI: 0.85-2.34) we found no significant difference in I/D genotypes between patients with CVI and controls. This study shows that in a group of Slovenian CVI patients the DD genotype is not an important risk factor for the development of stroke.