The latent HIV-1 reservoir represents a major barrier to achieving a long-term antiretroviral therapy (ART)-free remission or cure for HIV-1. Natural Killer (NK) cells are innate immune cells that play a critical role in controlling viral infections and have been shown to be involved in preventing HIV-1 infection and, in those who are infected, delaying time to progression to AIDS. To identify associations between markers of HIV-1 persistence and the NK cell receptor-ligand repertoire, we used twin mass cytometry panels to characterize the peripheral blood NK receptor-ligand repertoire in individuals with longterm antiretroviral suppression enrolled in the AIDS Clinical Trial Group A5321 study. Samples taken from people living with HIV-1 on long-term ART over the course of 50 weeks were profiled by CyTOF using antibody panels focused on natural killer cell receptors and ligands.