It is not known whether apolipoprotein E ε4-an Alzheimer disease susceptibility gene-influences the effects of state-anxiety on executive functioning in healthy individuals. In a prospective cohort study of 185 cognitively normal individuals, there were ε4 homozygotes, heterozygotes, and non-carriers, who did not differ in age, sex, years of education, cognitive test scores, psychotropic medications, and state- or trait-anxiety. However, higher anxiety was associated with significantly worse Trails B performance in the ε4 homozygotes, as compared with ε4 non-carriers. The association of executive-functioning difficulties and anxiety appears more likely to occur in persons who are most at risk for subsequent cognitive decline.