Both apolipoprotein-E (apo-E) epsilon 4 allele and angiotensin-converting enzyme (ACE) deletion (D) polymorphism have been associated with a high risk for coronary heart disease. Increased frequency of the epsilon 4 allele has also been reported in patients with late-onset of familial and sporadic Alzheimer's disease (AD). The primary aim of this study is to examine the possible relationship between the ACE gene polymorphism and AD. The second aim of this study is to explore the relation of the ACE and apo-E genotypes with AD. Polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP), and agarose gel electrophoresis techniques were used to determine the apo-E and ACE genotypes. The frequencies of ACE D and ACE insertion (I) allele among AD patients and controls were 55.7 percent versus 44.2 percent and 51.7 versus 48.2 percent, respectively. Apo-E allele frequencies in the AD group for epsilon 2, epsilon 3 and epsilon 4 were, 1.7 percent, 96.5 percent, and 1.7 percent, respectively. The apo-E allele frequencies of healthy groups for epsilon 2, epsilon 3 and epsilon 4 were 1 percent, 56 percent, and 1.7 percent, respectively. In conclusion ACE D and apo epsilon 4 allele were found to be more frequent in patients with Alzheimer's disease than in the control group.