Castello is a surname. Notable people with the surname include:
Bernardo Castello (1557–1629), Italian Mannerist painter
Dario Castello (c. 1590 – c. 1658), Italian composer
Felix Castello (1595–1651), Spanish Baroque painter
Giovanni Battista Castello (c. 1500 – c. 1579), Italian painter
Marie Castello (1915–2008), American psychic
Sebastian Castellio (also spelled Castello, 1515–1563), French theologian
Valerio Castello (1624–1659), Italian Baroque painter