Born in New York City and brought up in Brooklyn. He was often arrested as a youth for petty crimes and eventually he was sent to Tryon School in upstate New York where he was taught to box by Bobby Stewart. Tyson proved to be a natural and his physical development (he weighed 200lb at age 13 and was strong rather than fat) only aided his cause. Stewart knew the respected trainer Cus D'Amato and in 1980 D'Amato was introduced to the boy.
Tyson made his debut in the professional ring on March 6, 1985 in Albany, New York. He won the fight in a single round. He had a further fifteen fights in 1985 winning them all by knock-out (KO) or technical knock-out (TKO) and almost all in the first round. He fought twelve times in 1986, cutting a dangerous path through improving ranks of journey-man fighters and already attracting attention and courting media controversy (v. Jesse Ferguson). On November 22, 1986 Tyson was given his first title shot, fighting Trevor Berbick for the WBC heavyweight title it took Tyson two rounds to become the youngest heavyweight champion ever.
In 1987 Tyson defended his title against James 'Bonecrusher' Smith on March 7 in Las Vegas, Nevada. He won on a unanimous points decision and added Smith's WBA title to his existing belt. 'Tyson mania' in the media was becoming rampant. He beat Pinklon Thomas in May with a KO in the sixth round. On August 1 he took the IBF title from Tony Tucker, winning on points to became "undisputed heavyweight champion of the world". His only other fight in 1987 was in October against the 1984 Olympic champion Tyrell Biggs, it was an workmanlike performance from Tyson ending with a seventh round TKO.
Tyson had three fights in 1988. He faced an aged and flabby Larry Holmes on January 22 which finished with a fourth round TKO. He fought an even flabbier man in Tony Tubbs in Tokyo in March, fitting in a easy two round demolition amid promotional and marketing work. On June 27 he produced a unexpectedly good performance against Michael Spinks, Spinks lasted fractionally over 90 seconds before his KO. Tyson's problems outside boxing were starting to gain prominence, his marriage to Robin Givens was heading for divorce, and his future contract was being clawed over by Don King and Bill Cayton.
In 1989 Tyson had only two fights amid personal turmoil. He faced the popular but limited British boxer Frank Bruno in February in a below-par fight over five rounds and a pointless one round 'clash' with Carl Williams in July.
By 1990 Tyson had lost direction, his personal life was in disarray and he was not training well. In a fight on February 11 with the little regarded James 'Buster' Douglas he lost to a tenth round KO and despite the protests of his manager over a 'slow count' in the eighth round Tyson lost all his belts to Douglas. Tyson's two other fights in 1990 were confidence regaining first round KOs.
In 1991 Tyson fought Donovan Ruddock twice, once in March and again in June. There was some controversy over the first fight which Tyson won in the seventh round but at the second fight, which Tyson fought while waiting for a match against the new champion Evander Holyfield, Tyson won on points.
Tyson went on trial charged with the rape of a 1991 Miss Black America Contest contestant named Desiree Washington on January 27, 1992 and was found guilty of the rape on February 10 and imprisoned. As a result, Tyson did not fight again until 1995. As a Get-out-of-jail opener he won within one round against Peter McNeeley in August and beat Buster Mathis Jr. in three in December. In March 1996 Tyson regained one belt, winning the WBC title from a lumbering Frank Bruno in three rounds. In September Tyson won back the WBA in 93 seconds from Bruce Seldon, having paid Lennox Lewis $4m to 'step-aside'. On November 9 however he faced a tougher challenge in Evander Holyfield, fighting over eleven rounds Holyfield won with a TKO to become a three-times world champion.
Tyson did not fight again until June of 1997 when there was a hugely anticipated rematch with Holyfield on June 28 for the WBA title. Tyson was disqualified in the third round, he lost his temper over a head-butt from Holyfield and had come out without his gum-shield, he then bit a chunk from Holyfield's ear, when the referee, Mills Lane, warned him Tyson went for Holyfield's other ear. On July 9 Tyson was banned from boxing for one year and fined $3m.
In January 1999 Tyson fought the South African Frans Botha and while Botha initially controlled the fight Tyson landed a single good punch in round five that put Botha down. On February 5 Tyson was sentenced to a year's imprisonment, fined $5,000, and ordered to serve 2 years probation and perform 200 hours of community service for the August 31, 1998 assault on two people after a car accident. He served nine months of that sentence. On his release he fought Orlin Norris in October, where in a farcical scene Norris claimed to have twisted his ankle in the first round and refused to fight on.
In 2000 Tyson had three fights. The first was staged in England and against Julius Francis, the pre-fight arguments about whether Tyson should be allowed into the country were more entertaining than the second round KO of Francis. He also fought Lou Savarese in June in Glasgow, winning in the first round and in October the notoriously dirty Andrew Golota, winning in round three. Tyson fought only once in 2001 beating Brian Nielsen in Copenhagen with a seventh round TKO.
Tyson sought to fight Lennox Lewis in 2002 in Nevada but the Nevada boxing commission refused him a license to box as he is facing possible sexual assault charges. A scuffle at a press conference finally removed any chance of a Nevada fight. The fight actually occurred in June in Memphis, Tennessee. Tyson losing in the eighth round by knockout.
On February 22, 2003, Tyson beat fringe contender Clifford Etienne 49 seconds into round one, once again in Memphis. The pre-fight was marred by rumours of Tyson's lack of fitness and that he took time out from training to party in Las Vegas and have a new facial tattoo. Tyson is looking for a rematch with Lewis and contracts have been signed.
In August 2003, after years of financial struggles, Tyson finally filed for bankruptcy.
Tyson's record stands at 50 wins, 4 losses and 2 no contests, with 43 knockout wins.