Floyd Mayweather Praises 'Best President' Donald Trump

America has never had a better president occupying the White House, according to boxing legend Floyd Mayweather ... who says Donald Trump is the "best president" in U.S. history!

Mayweather appeared on FOX Business Wednesday afternoon, where he spoke glowingly about the 47th President of the United States.

"We had Trump before, we didn't appreciate him," Floyd told host Charles Payne, adding ... "but I think Trump is a great president. Actually, he's the best president in my eyes. He's the best president we ever had."

Mayweather, who attended Trump's first inauguration in 2017, acknowledged the people who dislike POTUS ... while making it clear DJT is exactly where he should be -- 1600 Pennsylvania Avenue.

"Trump has done an amazing job. A lot of people around America are upset, but no matter who goes in the White House, we're always upset. I think Trump is the man for the job. He's the best president in my eyes."

Mayweather, fresh off a week-long, lavish 48th birthday celebration in Miami, also spoke about his extensive real estate portfolio, worth hundreds of millions of dollars.