Alonso Valiente (Medina de las Torres 1482? - Nueva España 1564?) was a Spanish conqueror. He was Hernán Cortés' cousin and secretary. He was one of the first governors (Alguacil Mayor) of Mexico City. He was also the first encomendero of Tecamachalco, and he contributed to found Puebla de los Ángeles, where he also served as mayor.
Alonso Valiente first traveled to the New World with Cristóbal Colón's (Christopher Colombus') last expedition to the continent. He arrived in Santo Domingo in 1508 with Don Diego Colón. Valiente was one of the conquerors of Higüey in today's Dominican Republic and Borinquen (named by Cristóbal Colón San Juan Bautista) in what is now known as Puerto Rico He remained there from 1509 to 1521. He, his household, and sixty Spaniards he provisioned, arrived in Mexico City, only four months after the Spanish capture of the city. Valiente participated in the conquest of Michoacán and Pánuco. In 1524 he was also a part of Cortés' expedition to Las Hibueras in today's Honduras. This is evident in the appointment of Bernal Díaz as a captain, a document that was signed by Alonso Valiente. There, Valiente helped to conquer the three islands of Guanaja, in the coast of North Honduras. The inhabitants of these islands told that the crew of a vessel coming from today's Cuba had captured and enslaved more than sixty people. Probably being faithful to the Laws of Burgos, Cortés then ordered Valiente and others to go and rescue these people. He gave him a brigantine and the best artillery that was available. Valiente's expedition did not manage to capture the slavers. However they learned that the ship was originally sent from Santo Domingo with other purposes, but the captain changed plans during the mission, realizing that he could capture slaves and make a profit. Alonso Valiente is also one of the discoverers of the Old Bahama Channel. Valiente also participated in the conquest of Chametla in Nueva Galicia.