Aging is a progressive physiological process that involves alterations in the population of normal gutGut microbiotaGut microbiota. HIV infectionHIV infection in conjunction with agingAgeing complicates the quality of immune responses paving way for increased epithelial permeability and translocation of commensals and pathogen-derived substances into the systemic circulation. Enteric dysbiosisDysbiosis is linked with other comorbidities of agingAging including cardiovascular diseases and dementia in the HIV-infected population. The diversity of gutGut microbiotaGut microbiota declines with ageAge, and HIV infectionHIV infection compromises the effective functioning of the immune system complicating the metabolic as well as regulatory programming of the host’s physiological machinery. Given the scenario of the global HIV/AIDS and the COVID-19 pandemics, it is also likely that alterations in gutGut microbiotaGut microbiota potentially could contribute to post-acute COVID-19 syndrome as well as accelerate the rate of HIV disease progression. The current chapter discusses the role of normal gutGut microbiotaGut microbiota in the aged HIV-infected population and their functional implications in normal cellular and molecular mechanisms in the host.