If Logan Paul and Mike Tyson eventually fight in a celeb boxing match ... the YouTube star says he'd win -- exclaiming this weekend, "I would f***ing beat Mike Tyson."
The former heavyweight champ has been rumored to be a possibility for Paul's next big boxing match ... and Logan made it clear to media members Saturday that he'd beat the fighting legend if they met in the ring.
"He's too old," Paul said of Tyson ... "He's aging. Father time takes a toll on everyone."
If you're wondering, Paul is 26 while Tyson is 55 -- and Paul seems to believe that age gap would give him a chance.
"I got the reflexes of a cat," Logan said. "Like a young, quick feline, brother."
Paul hasn't fought since he went 8 rounds with Floyd Mayweather back in June ... but he says that bout is the reason he'd have confidence going into a Tyson fight.
"We saw with Floyd, dude," Paul explained. "There's no f***ing reason that I should have been able to last -- not just last, Floyd's on my highlight reel dog. There's no reason that should be possible."
Unclear when and where the fight would go down -- Paul seems to be still mulling over with it'd be a worthwhile match -- but Tyson's made it known he is interested in the tilt, saying last month "hell yeah" he'd fight the older Paul bro.