At the
2011 World Championships, he captained the Cuban national team, where he beat number 1 seeded
Egor Mekhontsev from Russia on points (21–15) in semi-final, and defeated
Adilbek Niyazymbetov from Kazakhstan after 3 rounds by 17–13 finishing score in final, being the 4th World amateur boxing champion boxer from
Camagüey. He grasped the gold medal at
2011 Pan American Games in which Cuba national team topped the medal table with 8 golds and 1 silver. He beat
Carlos Gongora of Ecuador in the semi-finals and
Yamaguchi Falcão Florentino of Brazil in the final on points (22–12). At the
2012 Summer Olympics, he was upset by Falcão Florentino in the quarterfinals in a rematch from the 2011 Pan American Games. At the
2013 World Championships in Almaty, he beat
Serge Michel, Oleksandr Ganzulia,
Abdelhafid Benchabla and
Joe Ward, before again beating Niyazymbetov in the final. On 4 January 2014, Julio Cesar la Cruz was hospitalized after being shot outside of a recreation center in his hometown of Camagüey. In 2015, he again won the gold at the
AIBA World Boxing Championships held in
Doha. He won the gold medal at the
men's light heavyweight event at the
2016 Summer Olympics. La Cruz sports a 21–3 record in the
World Series of Boxing. In the
2020 Summer Olympics, he gained attention for expressing his support for the Cuban government by declaring after his quarterfinal win over a Cuban-born Spanish opponent, "
Patria y vida, no. ¡
Patria o Muerte, Venceremos!", citing the national motto of Cuba which was created by Fidel Castro. In 2021, he again won the gold at the
men's heavyweight held in
Tokyo. ==Professional boxing record==