Tyson Fury is hangin' up his boxing gloves ... the 34-2 heavyweight superstar announced he's retiring!
The 36-year-old boxer made the big announcement on Monday, weeks after suffering a unanimous decision loss to Oleksandr Usyk ... in a 12-round heavyweight clash in Riyadh.
It was Fury's second loss to Usyk ... representing the only two losses of his soon-to-be Hall of Fame career.
"I'm going to make this short and sweet," Fury said in an Instagram video, "I'd like to announce my retirement from boxing.