Cruiserweight (also known as Junior Heavyweight) is a weight class in professional boxing. Weight classes are categories in which competition is divided into to match competitors of the same size against each other. It is a weight class between light heavyweight and heavyweight. In professional boxing, 200 pounds (90.7 kg) is the limit that a cruiserweight boxer can weigh in at. Initially, when the weight class was established, the weight limit was 190 pounds.
The division was established to allow heavyweight boxers who were of a smaller build and hence could not compete with the growing size boxers of that division. Even though Rocky Marciano and Joe Louis were great heavyweight champions and weighed about 190 pounds, in the 1970s, 220 to 230 pounds was made the standard weight for boxers to compete in the heavyweight division. Most of the boxing authorities felt that it was not fair to have men weighing between 176 pounds and 190 pounds fight larger men who weight about 220 to 230 pounds.
The first boxing organization to recognize this division was the WBC (World Boxing Committee). The organization was the first to sanction a match between Mate Parlov and Marvin Camel for its version of the title on 8 December 1979. This match ended in a draw but the rematch was scheduled to take place in March 1980. Camel beat Parlov in this bout to become the first cruiserweight champion.
The World Boxing Association (WBA), in 1982, recognized their first cruiserweight champion as Ossie Ocasio when he beat the South African Robbie Williams. In 1983, the International Boxing Federation (IBF) crowned their inaugural cruiserweight champion as Marvin Camel when he defeated Rick Sekorski.
After winning world titles in the cruiserweight division, many boxers moved up to the heavyweight category. Evander Holyfield was the first boxer to unify the WBA, WBC and IBF titles to become the undisputed champion and moved up to the heavyweight division in 1988.
Bobby Czyz, Tomasz Adamek, Virgil Hill, Al Cole, Orlin Norris, James Toney and David Haye are other notable champions in the division.
The record for the most consecutive title defenses is jointly held by Marco Huck and Johnny Nelson, with both achieving 13 defenses of the WBO title.
The following table lists the current champions of each sanctioning body.
| Sanctioning Body | Reign Began | Champion | Record | Defenses |
| WBA | May 31, 2019 | Arsen Goulamirian | 26–0 (18 KO) | 2 |
| WBC | January 31, 2020 | Ilunga Makabu | 29–2 (25 KO) | 2 |
| IBF | July 2, 2022 | Jai Opetaia | 22–0 (17 KO) | 0 |
| WBO | March 20, 2021 | Lawrence Okolie | 18–0 (14 KO) | 2 |
