Michael Gerard "Mike" Tyson (/ˈtaɪsən/; born June 30, 1966) is an American former professional boxer. He held the undisputed world heavyweight championship and holds the record as the youngest boxer to win the WBC, WBA and IBF heavyweight titles at 20 years, 4 months, and 22 days old. Tyson won his first 19 professional bouts by knockout, 12 of them in the first round. He won the WBC title in 1986 after defeating Trevor Berbick by a TKO in the second round. In 1987, Tyson added the WBA and IBF titles after defeating James Smith and Tony Tucker. This made him the first heavyweight boxer to simultaneously hold the WBA, WBC and IBF titles, and the only heavyweight to successively unify them.

In 1988, Tyson became the lineal champion when he knocked out Michael Spinks in 91 seconds. Tyson successfully defended the world heavyweight championship nine times, including victories over Larry Holmes and Frank Bruno. In 1990, he lost his titles to underdog James "Buster" Douglas, by knockout in round 10. Attempting to regain the titles, he defeated Donovan Ruddock twice in 1991, but pulled out of a fight with undisputed heavyweight champion Evander Holyfield due to injury. In 1992, Tyson was convicted of raping Desiree Washington and sentenced to six years in prison but was released after serving three years. After his release, he engaged in a series of comeback fights. In 1996, he won the WBC and WBA titles after defeating Frank Bruno and Bruce Seldon by knockout. With his defeat of Bruno, Tyson joined Floyd Patterson, Muhammad Ali, Tim Witherspoon, Evander Holyfield, and George Foreman as the only men in boxing history to that point to have regained a heavyweight championship after having lost it. After being stripped of the WBC title, Tyson lost his WBA crown to Evander Holyfield in November 1996 by an eleventh-round TKO. Their 1997 rematch ended when Tyson was disqualified for biting part of Holyfield's ear off.

In 2002, he fought for the world heavyweight title at the age of 35, losing by knockout to Lennox Lewis. Tyson retired from professional boxing in 2006, after being knocked out in consecutive matches against Danny Williams and Kevin McBride. Tyson declared bankruptcy in 2003, despite having received over $30 million for several of his fights and $300 million during his career. At the time it was reported that he had approximately $23 million of debt. Tyson was well known for his ferocious and intimidating boxing style as well as his controversial behavior inside and outside the ring. Nicknamed "The Baddest Man on the Planet", "Kid Dynamite", and "Iron Mike", Tyson is considered one of the best heavyweights of all time. He was ranked No. 16 on The Ring's list of 100 greatest punchers of all time, and No. 1 in the ESPN.com list of "The hardest hitters in heavyweight history". Sky Sports rated him as "the scariest boxer ever" and described him as "perhaps the most ferocious fighter to step into a professional ring." He has been inducted into the International Boxing Hall of Fame and the World Boxing Hall of Fame.