註釋 Latinos in the United States bear a disproportionate burden of HIV, suffering a three-fold incidence as compared to Non-Latino Whites (NLWs). People living with HIV (PLHIV) experience high levels of depression, which has been associated with antiretroviral therapy (ART) non-adherence in several meta-analyses; however, the relationship between depression and ART non-adherence has been studied very little among the Latino population. This study aimed to characterize the relationship between depression and ART adherence, and the role of substance use in mediating or modifying that effect, among Latinos. Using baseline survey data previously collected by Simoni et al. during an RCT [NCT01411839] in El Paso, Texas, 150 men who have sex with men (MSM) of Mexican descent were included in this cross-sectional analysis. Adherence, depression, and substance use were measured using the Simplified Medication Adherence Questionnaire (SMAQ), Beck Depression Inventory Version IA (BDI- IA), and the Addiction Severity Index (ASI-Lite), respectively. Using relative risk regression models we found that those with depression were 37% more likely to be non-adherent than those without depression [aPR: 1.37 (95%CI: 1.10-1.70), p = 0.006]. There was some evidence that substance use modified the effect of depression on adherence, and there was some evidence for mediation by substance use, but our power was limited to detect these effects. Our results indicate a need for more longitudinal studies to determine causality between depression and ART non-adherence in this high-risk group. 