Purpose: The purpose of this study was to explore risk factors for HIV and sexually transmitted infections (STIs) among transgender women (TW) in Lima, Peru. Methods: HIV-negative or serostatus unknown TW reporting recent condomless receptive anal intercourse underwent testing for STIs and HIV and completed a sociobehavioral survey. Results: Among 120 TW, 29.6% had rectal Neisseria gonorrhoeae (GC) or Chlamydia trachomatis (CT) and 12.6% had HIV. Age and migrant status were associated with rectal GC/CT, and rectal GC/CT predicted HIV infection. Conclusions: Further study is needed to understand individual and social factors that contribute to HIV/STI vulnerability among TW.