Vassiliy Valeryevich Jirov (Russian: Васи́лий Вале́рьевич Жи́ров; born 4 April 1974), sometimes known as Vasily Zhirov, is a Kazakhstani former professional boxer who competed from 1997 to 2009, and held the IBF cruiserweight title from 1999 to 2003.

[3] As an amateur he won a gold medal at the 1996 Olympics,[4] as well as consecutive bronzes at the 1993 and 1995 World Championships, all in the light heavyweight division.

In December 1996, Jirov travelled to the United States, where he signed a contract with boxing promoter Bob Arum and began his career as a professional boxer.

Jirov made his debut as a professional on 18 January 1997, with a two-round knockout of Vince Brown in Las Vegas.

On 5 May he won the WBC's regional cruiserweight title with a 12-round decision over Rich La Montaigne, who became the first boxer to last the full distance against Jirov.

For his first defense, he fought at the main supportive event at the Felix Trinidad-Oscar De La Hoya undercard on 18 September, retaining the crown with a ten-round knockout of Canadian Dale Brown.

In 2000, he beat Saul Montana by knockout in round nine to retain the world title on an Univision televised fight, and won two non-title bouts, including one over Esteban Pizarro at the Playboy mansion.

[5] In 2002 Jirov, then managed by the Sugar Ray Leonard promotion company, defended his crown once that year, beating former world Middleweight champion Jorge Castro of Argentina by a 12-round decision on 1 February at the Celebrity Theater in Phoenix.

On 6 November 2003 he won the NABO regional cruiserweight title with a six-round knockout of Joseph Kiwanuka in Phoenix.