Lacayo is a surname, from the Spanish language it originally described a footman. Notable people with the surname include:
Benjamín Lacayo Sacasa (1893–1959), Nicaraguan politician and President of Nicaragua Ernesto Lacayo (born 1989), American football player José Antonio Lacayo de Briones y Palacios (1679–1756), Spanish general and colonial governor Júnior Lacayo (born 1995), Honduran footballer Marianela Lacayo (born 1981), Nicaraguan model and journalist Rafael Lacayo (born 1998), Nicaraguan sports shooter Rossana Lacayo (born 1956), Nicaraguan photographer, scriptwriter, and filmmaker