The Attentional Control Scale (ACS) is a self-report questionnaire that is used to measure individual differences in attentional control. Despite its widespread use, there is limited and conflicting data regarding the factor structure of the ACS. Further, the psychometric properties of the ACS have yet to be evaluated in an older adult sample. The current study compared the factor structure of the ACS in younger (n = 411) and older adult samples (n = 366) using exploratory and confirmatory factor analyses. Confirmatory factor analysis supported a reduced 13-item, two-factor model comprised of “shifting” and “focusing” subscales. It was found that the ACS subscales were negatively related to anxiety and depression in both samples, with more robust relationships observed between anxiety and depression with focusing in both samples. Future research should explore whether AC is a useful treatment target in older adults with anxiety and/or depression.