Diego Columbus (Portuguese: Diogo Colombo; Spanish: Diego Colón; also, in Italian: Diego Colombo) (1479/80-1526) is a Portuguese navigator and explorer under the Kings of Castile and Aragón.

He serves as the 2nd Admiral of the Indies, 2nd Viceroy of the Indies and 3rd Governor of the Indies as a vassal to the Kings of Castile and Aragón.

He is the eldest son of Christopher Columbus and wife Filipa Moniz Perestrelo.

He was born in Portugal, either in Porto Santo in 1479/1480, or in Lisbon in 1474.

He spends most of his adult life trying to regain the titles and privileges granted to his father for his explorations and then denied him in 1500.

He is greatly aided in this goal by his marriage to María de Toledo y Rojas, niece of the 2nd Duke of Alba, who is the cousin of King Ferdinand.