He turned professional in 1977. On March 24, 1980, at the age of 21 and with a record of 10-1, Zapata won the World Boxing Council minimum title in Japan when defeated Shigeo Nakajima.
He defended his title 8 times on his opponent backyards; He made an average of four fights a year.
In 1982 he loses his title with Amado “Panterita” Ursúa, to regain the title five months later from Tadashi Tomori in Japan. He lost this title with the Korean Jung Kwo Chang after two successful
Moves to Flyweight division and defeats Alonzo González to win the world title for the third time. This time he conquered the World Boxing Association belt. He loses the title with Fidel Bassa in Barranquilla, Colombia, with whom he would draw in a rematch bout.
Hilario Zapata retired after 16 years in boxing, with a record of 43-10-1, 10
- He participated in 24 world title fights, which places him ahead of Roberto Durán and Eusebio Pedroza.
- He was three-time world champion in two organizations.
- He fought 303 rounds of title fights, right behind Emile Griffith (339) and Abe Atell (337).