Diego Garcia is an atoll located south of the equator in the central Indian Ocean. Diego Garcia is the largest of the 60 small islands comprising the Chagos Archipelago. Diego Garcia was settled by the French in the 1790s and was transferred to British rule after the Napoleonic Wars. It was one of the "Dependencies" of the British Colony of Mauritius until it was detached for inclusion in the newly created British Indian Ocean Territory (BIOT) in 1965. Between 1968 and 1973, the population of the BIOT was removed to Mauritius and The Seychelles, following which the United States built a large naval and military base on Diego Garcia, which has been in continuous operation ever since. As of March 2015, Diego Garcia is the only inhabited island of the BIOT; the population is composed of military personnel and supporting contractors.

Diego Garcia is an atoll in the Chagos Archipelago, a part of the British Indian Ocean Territory. Diego Garcia may also refer to:

• Diego García Bravo (born 1990), Spanish football goalkeeper
• Diego García (taekwondo) (born 1990), Mexican taekwondo practitioner
• Diego García (athlete) (1961–2001), Spanish long-distance athlete
• Diego García (racewalker) (born 1996), Spanish race walker
• Diego García (basketball) (born 1979), Argentine professional basketball player
• Diego García (footballer) (born 1987), Mexican football defender