The purpose of this study was to examine the impact of two polymorphisms (rs4291A>T and rs4343G>A) in the ACE gene on the risk of Alzheimer's disease (AD), using a population-based cohort of 9294 subjects selected from the electoral rolls of three French cities (the Three-City Study). Two follow-up examinations took place 2 and 4 years after inclusion. Diagnosis of dementia was assessed at baseline and at each follow-up examination by neurologists independent of the 3C Study group. For the present analysis, subjects whose mother tongue was not French, those from abroad and those lost at follow-up were excluded, leaving a sample of 6791 subjects. 108 subjects were demented at baseline and 216 subjects, among which 141 had AD, developed a dementia during follow-up. The genotype distributions of the ACE SNPs rs4291 and rs4343 did not differ according to cognitive status. After adjustment for confounding variables, the risk of developing AD was similar whatever the genotype (rs4291 AT vs TT: OR=0.90, p=0.65; AA vs TT: OR=1.05, p= 0.84; rs4343 GA vs GG: OR=1.15, p= 0.48; AA vs GG: OR=1.25, p= 0.37). No global haplotype effect could be observed on the risk of AD.