Callao (disambiguation)

Callao may refer to:

;Place Names
*Callao, the largest port city of Peru, located in Callao District.
* Callao District (Peru), found in Constitutional Province of Callao
* Callao Region (Peru), coterminous with Constitutional Province of Callao
* Constitutional Province of Callao (Peru), coterminous with Callao Region
* Callao, Missouri (United States)
* Callao, Utah (United States)
* Callao, Virginia (United States)
* "Plaza de Callao" and the underlying Madrid Metro station, in Madrid, Spain.

;Military History
* Battle of Callao, 1866 naval battle between Spain and Peru (and her allies)
* Bombardment of Callao, a naval blockade and bombardment of the city of Callao, Peru, from April 1880 to January 1881 by the Chilean navy during the War of the Pacific which resulted in the surrender of the city to the advancing Chilean army.

;Ships
*"Callao", a Spanish Navy gunboat that fought in the Spanish-American War.
*USS "Callao" (YFB-11), a U.S. Navy gunboat captured from Spain and in U.S. service from 1898 to 1923.
*USS "Callao" (ID-4036), a U.S. Navy transport in service in 1919.
*USS "Callao" (IX-205), a U.S. Navy ship captured from the German Navy and in U.S. service from 1945 to 1950.