Background: The widespread success of antiretroviral therapy (ART) has transformed HIV into a chronic condition, shifting clinical attention toward aging-associated comorbidities, including autoimmune and rheumatologic diseases. However, the epidemiology, clinical spectrum, and treatment outcomes of these conditions in older people living with HIV (PLH) remain incompletely characterized. Objective: This scoping review aimed to map contemporary evidence on autoimmune and rheumatologic diseases in aging PLH in the ART era, with emphasis on epidemiology, clinical phenotypes, diagnostic challenges, and therapeutic outcomes. Methods: A systematic search of PubMed, Embase, and Scopus was conducted for studies published from January 1, 2021, onward. Eligible studies included adult PLH with autoimmune or rheumatologic conditions and were screened according to PRISMA-ScR methodology. Case reports, non-human studies, and studies published before 2021 were excluded. Data were extracted narratively from included studies. Results: The search yielded 438 records, of which 134 duplicates were removed. After title, abstract, and full-text screening, 8 studies were included. The evidence identified a heterogeneous spectrum of autoimmune and rheumatologic manifestations in PLH, including systemic lupus erythematosus, reactive arthritis, psoriatic arthritis, rheumatic heart disease, immune thrombocytopenia, renal immune-mediated pathology, and myasthenia gravis. Contemporary data suggest that biologic and targeted small-molecule therapies are generally effective and well tolerated in selected PLH, although opportunistic infections and transient viral load increases have been reported with some agents. Conclusion: Autoimmune and rheumatologic diseases in aging PLH represent an emerging ART-era challenge. Prospective studies and multidisciplinary guidelines are needed to optimize diagnosis and treatment.