Considering the lack of validated stigma reduction interventions for youth living with HIV (YLWH), we evaluated effects of the Healthy Choices intervention on HIV-related stigma among YLWH. We analyzed data from the Adolescent Medicine Trials Network protocol 129, multi-site randomized controlled trial, applying latent growth curve modeling with two linear slopes estimating changes in Berger’s Stigma Scale pre-intervention, 16, 28, and 52 weeks post-intervention, as well as the trajectory of stigma scores over the follow-up period (N = 183). Expected value for the growth intercept was statistically significant (B = 2.53; 95% CI 2.32, 2.73; p < 0.001), as were differences in the change from baseline to 16-week follow-up (B = - 0.02; 95% CI - 0.04, 0.01; p = 0.034). Expected value of the slope factor measuring growth over the follow-up period was non-significant suggesting that stigma scores were stable from 28 to 52 weeks. Our findings warrant replication and additional research comparing effects of this intervention to counterfactual controls.