However, a source close to the controversial former world heavyweight champion swiftly indicated they do not believe he has retired.
Fury declared he had been on an "epic journey" and suggested he was finished as a fighter. The 28-year-old has retired in the past though, only to then reverse the decision.
This time the source close to Fury told Press Association Sport the Manchester-born fighter is "fine" and is not expected to walk away from boxing.
Fury wrote on Instagram: "been very blessed in my life & career achieve the upmost in boxing, was a epic journey along the way. Thanks to all the fans that supported & believed in me along the way,
"Hope you enjoy it as much as I did. THE END."
Fury has not fought since his stunning win over Wladimir Klitschko in Dusseldorf in November 2015, due to a combination of drug issues and mental health concerns.
He vacated the WBA and WBO titles he held last October after admitting using cocaine to cope with depression, after which the British Boxing Board of Control (BBBofC) suspended his boxing licence.
Fury has been charged with the use of a prohibited substance by UK Anti-Doping (UKAD). In May, his National Anti-Doping Panel hearing was postponed, delaying a possible comeback.
The panel was due to rule on allegations Fury and his cousin and fellow heavyweight Hughie Fury tested positive for nandrolone in 2015.
Both men have strongly denied any wrongdoing and they were not charged with an anti-doping offence until June 24, 2016, the same day Tyson Fury postponed a rematch with Klitschko because of a sprained ankle.
He also announced last October that he had quit the sport, and described boxing as "the saddest thing I ever took part in".
But hours later he indicated it was a prank, writing on Twitter: "You think you will get rid of the Gypsy King that easy. I'm here to stay."
Fury became embroiled in a war of words with Anthony Joshua before and after Joshua's thrilling world title victory over Klitschko at Wembley Stadium in April.
He promised that he would beat Joshua with "one arm tied behind my back" and insisted that he is still the main man in heavyweight boxing.
Fury even went as far as to claim that Joshua's promoter Eddie Hearn had already booked Wembley Stadium for April 2018 to stage the fight.
But that lucrative showdown was put firmly on the backburner when the National Anti-Doping Panel hearing was put off to a later date.
The BBBofC later said that it would not lift Fury's suspension until the doping case is resolved.
Related links
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