He began his professional career at the age of 17 on December 8, 2007, with a four-round decision win over Corey Sommerville. On April 19, 2008, he stopped Jesus Villareal in three rounds and after scoring an impressive first-round TKO over Dwayne Jones in June, Charlo added the names Rodrigo Villareal (TKO4) and Deon Nash (W6) to his victims list before the year was out. In 2009, he scored a shutout four-round decision over Juan Serrano on February 28, got a decision win over Carlos Garcia over six rounds on April 4, TKO’d Federico Flores Jr. in the eighth round on June 26, defeated Vardan Gasparyan in six, and then finished up the year with a second-round knockout of unbeaten prospect Abdon Lozano.
Charlo scored a sensational one-punch knockout of Chicago’s Chris Chatman in the third round. Chatman’s only previous loss was a six-round decision to 2008 U.S. Olympian Demetrius Andrade in 2009, but he was no match for Charlo, who controlled his awkward opponent for most of the fight. In the third round, he landed a flush straight right hand to Chatman’s chin and knocked him out at 1 minute, 22 seconds. With this win, at the age of 22, Charlo had a record of 17 wins, with no losses with 8 wins inside the distance.
On June 8, 2013, Charlo fought former light welterweight contender Demetrius Hopkins (33-2-1, 13 KOs). In a close back and forth affair were Charlo controlled the action in the early rounds with his aggression and power shots, he defeated Hopkins by unanimous decision. All three judges scored it 115-113. The crowd seemed to be displeased with the performances.
Charlo next fought in October against 34 year old Jose Angel Rodriguez (17-2-1, 2 KOs) in a scheduled 10 round fight at the BB&t Center in Sunrise, Florida.Charlo won the fight in the last round via TKO.