Engagement in the HIV care continuum among people living with HIV is essential to prevent ongoing transmission. Although there is evidence for the need for comprehensive approaches (e.g., peer navigation) to improve the HIV care continuum, there is limited knowledge of how the peer navigation model might work to improve the HIV care continuum in low resource settings among Latinx key populations (e.g., persons who inject drugs, female sex workers, men who have sex with men, and transgender women). Therefore, this article aims to qualitatively assess members of key populations' acceptability of (Healthy Connections), a community-based peer navigation intervention implemented in Tijuana, Mexico. This analysis draws upon the postintervention survey data from 34 participants and data from qualitative interviews with 10 participants. Participants found the intervention to be acceptable and discussed the ways in which peer navigators were influential in educating participants about HIV, antiretroviral therapy (ART), linking participants to existing HIV care and ancillary services in Tijuana, and in providing emotional and instrumental support to facilitate engagement in HIV treatment and ART adherence. The intervention emphasized the use of peer navigators who had a deep understanding of the sociostructural barriers (e.g., substance use, homelessness) that HIV-positive key populations face in Tijuana. Findings from this study may inform programs with highly vulnerable populations in similar settings.