After turning professional in 1999, it has been full-steam ahead for Brazilian lightweight fighter Gleison Tibau, as he has put together one of the most complete records in the UFC lightweight division, defeating top welterweight Thiago Alves before either of them were in the Zuffa, LLC fold. Since his UFC debut in 2006, Tibau has been thrown in the pit with the division's young lions, and come out with victories over Rafael Dos Anjos, Jamie Varner, Jeremy Stephens, Josh Neer, and Caol Uno, among others.

A Brazilian Jiu-Jitsu Black Belt who trains out of one of the most aggressive and well-trained fight teams in the United States, American Top Team, Tibau is known predominantly for his physical size and strength in the lightest weight division in the UFC. He is known to cut an extraordinary 30 lbs. to make 155, and when he cuts well, he usually demonstrates complete physical dominance over his opposition. It can seem virtually inconceivable by fight time that the enormous Gleison Tibau could weigh only 155 for even a few brief moments, but the scales do not lie. In his fight with Neer at UFC 104, Tibau simply tossed Neer around the ring at will for three rounds to take a unanimous decision. It was a similar story against Uno, as the highly skilled Japanese grappler was simply overwhelmed by Tibau's size, strength and power, bowing out to a barrage of strikes in the first frame. Tibau was on a 6-2 run with his only defeats coming to top contenders Khabib Nurmagomedov and Evan Dunham. He took on Michael Johnson at UFC 168 but was stopped by knockout in the second round.

TIbau has gotten back on track since losing the Michael Johnson fight, He controlled Pat Healy for 15 minutes to win by Unanimous Decision at UFC Fight Night 45: Cerrone vs. Miller. His next bout against Piotr Hallmann at UFC Fight Night 51: Bigfoot vs. Arlovski 2 he won via split decision in a very exciting fight, which got both Tibau and Hallmann $50,000 FOTN honours.

Tibau would continue his decision victory pattern with another entertaining split decision win over Norman Parke at UFC Fight Night 59: McGregor vs. Siver. This 3 fight win streak come to an explosive end when Tibau filled in for injured Yancy Medeiros, at UFC 184: Rousey vs. Zingano. Tibau faced Tony Ferguson, Tibau was quickly defeated via Rear Naked Choke at 2:37 in Round 1.