Background: Antidepressant drugs are among the most widely prescribed drugs in the United States; however, little is known about their use among major ethnic minority groups. Method: Collaborative Psychiatric Epidemiology Surveys (CPES) data were analyzed to calculate nationally representative estimates of Latino and non-Latino White adults antidepressant use. Setting: The 48 coterminous United States was the setting. Participants: Household residents aged 18 years and older (N=9,250). Main outcome: Past year antidepressant use. Results: Compared to non-Latino Whites, few Latinos, primarily Mexican Americans, with 12-month depressive and/or anxiety disorders reported past year antidepressant use. Mexican Americans (OR=0.48; 95%CI=0.30?0.77) had significantly lower odds of use compared to non-Latino Whites, which were largely unaffected by factors associated with access to care. Over half of antidepressant use was by respondents not meeting 12-month criteria for depressive or anxiety disorders. Lifetime depressive and anxiety disorders explained another 21% of past year antidepressant use, leaving another 31% of drug use unexplained. Discussion: We found a disparity in antidepressant use for Mexican Americans compared to non-Latino Whites that was not accounted for by differences in need and factors associated with access to care. About one third of antidepressant use was by respondents not meeting criteria for depressive or anxiety disorders. Our findings underscore the importance of disaggregating Latino ethnic groups. Additional work is needed to understand the medical and economic value of antidepressant use beyond their primary clinical targets. Depression and Anxiety, 2009. Published 2009 Wiley-Liss, Inc.