During 2018, estimated incidence of human immunodeficiency virus (HIV) infection among Hispanic and Latino (Hispanic/Latino) persons in the United States was four times that of non-Hispanic White persons (1). Hispanic/Latino men who have sex with men (MSM) accounted for 24% (138,023) of U.S. MSM living with diagnosed HIV infection at the end of 2018 (1). Antiretroviral therapy (ART) adherence is crucial for viral suppression, which improves health outcomes and prevents HIV transmission (2). Barriers to ART adherence among Hispanic/Latino MSM have been explored in limited contexts (3); however, nationally representative analyses are lacking. The Medical Monitoring Project reports nationally representative estimates of behavioral and clinical experiences of U.S. adults with diagnosed HIV infection. This analysis used Medical Monitoring Project data collected during 2015-2019 to examine ART adherence and reasons for missing ART doses among HIV-positive Hispanic/Latino MSM (1,673). On a three-item ART adherence scale with 100 being perfect adherence, 77.3% had a score of ≥85. Younger age, poverty, recent drug use, depression, and unmet needs for ancillary services were predictors of lower ART adherence. The most common reason for missing an ART dose was forgetting; 63.9% of persons who missed ≥1 dose reported more than one reason. Interventions that support ART adherence and access to ancillary services among Hispanic/Latino MSM might help improve clinical outcomes and reduce transmission.