He is the son of former three-term Governor of Puerto Rico Rafael Hernández Colón.

Hernández Mayoral obtained his bachelor's degree in communications from the Universidad del Sagrado Corazón in 1992.

Hernández Mayoral received a Juris Doctor from (Pontifia Universidad Catolica de Puerto Rico) in 2021.

In 1996, he also worked as executive director of the annual conference of the Club of Rome.

An active member of the Puerto Rico Democratic Party, of which he serves as Secretary of its State Committee, he will be attending his seventh consecutive Democratic National Convention in Charlotte, North Carolina in September.