Pedro de Alvarado (Spanish pronunciation: [ˈpeðɾo ðe alβaˈɾaðo]; c. 1485 – 4 July 1541) was a Spanish conquistador, adelantado, governor and captain general of Guatemala. He participated in the conquest of Cuba, in Juan de Grijalva's exploration of the coasts of the Yucatán Peninsula and the Gulf of Mexico, and in the conquest of the Aztec Empire led by Hernán Cortés. He is considered the conquistador of much of Central America, including Guatemala, Honduras, El Salvador, and parts of Nicaragua.

While a great warrior, Alvarado developed a reputation for greed and cruelty, and was accused of various crimes and abuses by natives and Spaniards alike. In 1541, Alvarado was crushed by a horse while attempting to quell a native revolt in Mexico, dying a few days later.

Pedro de Alvarado was flamboyant and charismatic, and was both a brilliant military commander and a cruel, hardened man. He is described as having "good features and bearing", and when presented with a picture of him, the Aztecs referred to him as Tōnatiuh. The Aztecs gave Alvarado this name because of his blond hair, and also his infamous temper. He was handsome, and presented an affable appearance, but was volatile and quick to anger.

He was ruthless in his dealings with the indigenous peoples he set out to conquer. Historians judge that his greed drove him to excessive cruelty, and his Spanish contemporaries denounced his extreme brutality during his lifetime. He was a poor governor of territories he had conquered, and restlessly sought out new adventures.

His tactical brutality, such as the massacre in the Great Temple of Tenochtitlan, often undermined strategic considerations. He was also accused of cruelty against fellow Spaniards. Alvarado was little suited to govern; when he held governing positions, he did little to establish stable foundations for colonial rule. His letters show no interest in civil matters, and he discussed only exploration and war. Alvarado stubbornly resisted attempts by the Spanish Crown to establish ordered taxation in Guatemala, and refused to acknowledge such attempts. As governor of Guatemala, Alvarado has been described by W. George Lovell et al. as "an insatiable despot who recognized no authority but his own and who regarded Guatemala as little more than his personal estate."

American historian William H. Prescott described Alvarado's character in the following terms:

Alvarado was a cavalier of high family, gallant and chivalrous, and [Cortes'] warm personal friend. He had talents for action, was possessed of firmness and intrepidity, while his frank and dazzling manners made the Tonatiuh an especial favourite with the Mexicans. But, underneath this showy exterior, the future conqueror of Guatemala concealed a heart rash, rapacious, and cruel. He was altogether destitute of that moderation, which, in the delicate position he occupied, was a quality of more worth than all the rest.

— William H. Prescott 1922, History of the Conquest of Mexico: Book 4, Chapter 8, p. 54.