M
- Jason MacDonald – (MFC, UFC)
- Lyoto Machida – (NJPW, Jungle Fight Championship, K-1 HERO'S, WFA, UFC)
- Jon Madsen – (UFC)
- Demian Maia – (UFC)
- Ronnie Mann – (Bellator)
- Vladimir Matyushenko – (Jungle Fight Championship, Affliction, IFL, UFC)
- Sean McCorkle – (KOTC, UFC)
- Court McGee – (UFC)
- James McSweeney – (Cage Rage, BAMMA, UFC)
- Paul McVeigh – (Cage Rage, Cage Warriors)
- Jason "Mayhem" Miller (UFC, Strikeforce, Dream)
- Jim Miller – (Ring of Combat, UFC)
- Stipe Miocic – (UFC)
- Frank Mir – (UFC)
- Matt Mitrione – (UFC)
- Rafał "Kulturysta" Moks – (M-1)
- Daniel Moraes – (Jungle Fight Championship)
- Christian Morecraft – (UFC)
- Dave Morgan
- Johnnie Morton – (K-1 HERO'S)
- Gegard Mousasi – (StrikeForce, Dream, Deep, MFC, Pride, K-1)
- Mark Munoz – (WEC, UFC)
- Tom Murphy – (KOTC, UFC, TKO)
- Lee Murray – (Cage Rage, UFC)
Read more about this topic: List Of Male Mixed Martial Artists