Bernardo Castello (or Castelli) was an Italian painter of the late-Mannerist style, active mainly in Genoa and Liguria. He is mainly known as a portrait and historical painter.

Bernardo Castello was born in San Martino d'Albaro [it], now a quarter of Genoa. He was apprenticed under Andrea Semino and Luca Cambiaso, then travelled throughout Italy, meeting other painters and creating his own particular style.

During his career he painted many works and was appreciated by famous poets with whom he had friendships. Amongst these were Gabriello Chiabrera and Torquato Tasso, and Castello was the illustrator for Jerusalem Delivered by Tasso, published in 1590 (and also for a further edition, published in 1617). Some of these illustrations were engraved by Agostino Carracci.

Beside working in Genoa, Castello was employed in Rome and worked also for the Duke of Savoy, Charles Emmanuel I.

Bernardo Castello died in October 1629 aged seventy-two years following a short illness, as he was about to go to Rome, where he had been requested to paint a picture for St. Peter's Basilica. He was buried in the church of San Martino of Albaro.

Valerio Castello, was his youngest son. Valerio was only six when Bernardo died, but went on to become one of the greatest Genoese painters of the 17th centur