UFC Freedom 250's got more stars than the American flag ... and we've got a gallery capturing the crowd in all its glory.

Heavy hitters like Mackenzie Dern, Joshua Van and Diego Lopes pulled up to the prez's place Sunday evening before one of the most-anticipated events in sports.

Gilbert Burns put a fan in a headlock for a photo-op ... while Jean Silva stood next to his admirers, fists raised, for pics.

Dustin Poirier appeared on the pregame show ... flashing a grin at the crowd.

Caio Borralho, Josh Emmett, Randy Brown, Steve Garcia and more have also made it down to the event, way before the first bell.

Kyle Daukaus, Mauricio Ruffy and Derrek Davis -- all fighting tonight -- arrived without smiles ... sporting game faces instead.

While the stars came out to support, a ton of protesters came out as well -- including one who held a sign comparing President Donald Trump to Adolf Hitler.