Justin Ray Gaethje is an American professional mixed martial artist. He currently competes in the Lightweight division of the Ultimate Fighting Championship (UFC). A professional since 2011, he is a former UFC Interim Lightweight Champion and a former UFC "BMF" titleholder. Gaethje is the second fighter to win the BMF belt after Jorge Masvidal, winning the title at UFC 291. As of November 18, 2025, he is #4 in the UFC lightweight rankings. Gaethje formerly competed in the Lightweight division of the World Series of Fighting (WSOF), where he was the first and only WSOF Lightweight Champion.