Arrillaga is a surname. Notable people include:
Blanca Renée Arrillaga (1917–2011), Uruguayan chemist, botanist, professor and agrostologist Eduardo Arrillaga (born 1961), Mexican rower John Arrillaga (1937–2022), American real estate billionaire José Joaquín de Arrillaga, seventh (1792–1794) and tenth (1800–1814) governor of Alta California Laura Arrillaga-Andreessen, American philanthropist, daughter of John Maria Arrillaga, Puerto Rican poet