The association between prior seropositivity to human adenovirus (HAd) type 5 and increased HIV acquisition in the Step Vaccine Study has raised questions concerning the frequency of endemic HAd infection in adults. Few studies have documented the frequency and types of HAd infections in HIV-infected populations using sensitive molecular methods. In this study we retrospectively tested rectal swabs collected from a prospective cohort of Peruvian HIV-positive MSM for the presence of HAds.