Marcin Tybura (born November 9, 1985) is a Polish professional mixed martial artist. He currently competes in the Heavyweight division of the Ultimate Fighting Championship (UFC). A professional competitor since 2011, Tybura previously fought for M-1 and was an M-1 Global Heavyweight Champion and M-1 Grand Prix 2013 Heavyweight Champion. As of April 14, 2026, he is #12 in the UFC heavyweight rankings.

Tybura began training in 2006 after a friend introduced him to the sport. Within weeks, he began feeling the urge to compete. However, he would not make his professional debut until several years later.

He earned a Master's degree in Physical Education at the University of Łódź.

Tybura made his professional debut on November 5, 2011, against Robert Marcok, whom he beat by a rear-naked choke. He won his next five fights on the Polish MMA circuit, most notably defeating the future UFC heavyweight Adam Wieczorek by a unanimous decision. His last fight at the regional level was a third-round TKO of Krystian Kopytowski at Gladiator Arena 4.

In 2013, Tybura signed with the Russian based M-1 Global promotion. For his promotional debut, Tybura was scheduled to fight Denis Komkin as a Heavyweight Grand Prix alternate bout. He won the fight by TKO, after Komkin retired from the bout at the end of the first round.

Tybura was then scheduled to fight Chaban Ka at M-1 Challenge 41, in a Heavyweight Grand Prix Semifinal. He beat Ka by a first-round TKO.

In his next two fights, Tybura beat Konstantin Gluhov at M-1 Challenge 42 by rear-naked choke and Maro Perak at M-1 Challenge 47 by a third-round TKO.

At M-1 Challenge 50, Tybura fought Damian Grabowski in the M-1 Heavyweight Grand Prix finals. Tybura submitted Grabowski with a north-south choke 88 seconds into the first round, to become the M-1 Heavyweight champion. He was scheduled to make his first title defense against Denis Smoldarev at M-1 Challenge 53. Tybura successfully defended the title with a first-round submission.