BackgroundRacially diverse sexual minority men (SMM) are disproportionately impacted by the U.S. HIV epidemic. Substance use, particularly stimulant use, may impact viral suppression for SMM living with HIV. The current study sought to characterize patterns of substance use via latent class analysis (LCA) and test associations between those patterns and future viral load outcomes, among SMM living with HIV. MethodsData were drawn from Thrive With Me (TWM), an RCT of an mHealth intervention targeting ART adherence among SMM living with HIV. LCA was performed with six dichotomous indicators of substance use, derived from validated measures and urinalysis results, to determine substance use classes at baseline. Bivariate and multivariable logistic regression models tested associations between baseline substance use classes and HIV viral load 5-months post-baseline. ResultsAmong 383 SMM living with HIV, we identified a three-class model of substance use fit best: low probability substance use (81.3 %), high probability hazardous alcohol, marijuana, and cocaine use (7.5 %), and high probability methamphetamine and amphetamine use (11.2 %). Additionally, the high probability amphetamine use class was less likely to be virally suppressed at 5-month follow-up compared to the low probability substance use class [Adjusted Odds Ratio = 3.34, 95 % Confidence Interval = 1.39–7.99, p = .0069]. ConclusionWe identified that some patterns of substance use (i.e., methamphetamine and amphetamine use), but possibly not others (e.g., alcohol, marijuana, and cocaine use), are potentially important intervention targets for improving HIV-related outcomes among racially diverse SMM living with HIV.