Joseph "JoJo" Pedroza Diaz Jr. (born November 23, 1992) is a Mexican-American professional boxer who held the IBF super featherweight title from 2020 to February 2021.

Diaz made his professional debut in 2012 against Vincent Alfaro, winning by unanimous decision over four rounds and also scored a knockdown in the fourth.

He stepped up competition against veteran Rene Alvarado in a fight televised on HBO Latino in July 2015 and on December 18, Diaz Jr. defeated Hugo Partida and earned the WBC-NABF featherweight title.

[7] On January 30, 2020, Diaz defeated IBF super featherweight champion Tevin Farmer by unanimous decision with scores of 115–113, 115–113, and 116–112 to claim his first world title.

Diaz was docked a point in the fourth round for hitting behind the head, but nonetheless emerged as the victor via unanimous decision, with scores of 117–110, 116–111 and 115–112.

[11] On October 8, 2021, it was announced that Diaz would be defending his WBC interim lightweight title against its previous owner, undefeated Ryan García, in Los Angeles on November 27.