The 45th POTUS took to his social media platform Truth Social Thursday to address whether he'd go toe-to-toe with his opponent for president again ... equating the current VP to a prizefighter who just lost a huge bout -- who immediately demands a rematch.

DJT says he's the clear winner against "Comrade Kamala Harris" ... saying polls show he won.

Trump says Harris refused to debate him on Fox News, CBS and NBC already ... and, instead of debating him a second time, Trump says she should focus on fixing real issues in the country.

Trump previously debated President Joe Biden in June, leading to the incumbent dropping out of the race and Harris' subsequent nomination.

In the post, DJT slams Kamala and Joe Biden for their immigration policy, saying they're allowing criminals and mentally deranged people to roam the streets in the U.S., and calls out high inflation during their administration.

Tuesday night's debate was full of viral moments ... from the hesitant handshake that set the tone for the evening, to Trump's claims that immigrants are eating pet dogs and cats in Ohio.

While people have been split about the debate performance -- along party lines, unsurprisingly -- Harris certainly walked away with a big prize ... Taylor Swift's endorsement.