Justin Willis is a professional MMA fighter who fights in the heavyweight division of the Professional Fighters League. A professional competitor since 2012, he has formerly competed for the World Series of Fighting, Strikeforce and the UFC.

Willis made his pro debut in June of 2002 at Ring of Fire 43 against Henry Solis. Willis lost by TKO in the second round.

Willis next fought on June 14, 2014 facing James Kirby at Global Knockout - The Return. Willis won the fight by TKO in the first round.

Willis had his third professional fight on New Year's Eve 2014 in Tokyo, Japan at IGF Inoki Bom-Ba-Ye2014 where his disposed of Yusuke Kawaguchi in the first round by TKO.

Willis fought Rizvan Kuniev at IGF - Inoki Genome Fight 4 on August 29, 2015 where he won by unanimous decision, raising his professional record to 3-1.

Willis was featured in the television series Fight Factory in which he told his story of being a foster child, being moved to 23 different homes growing up, surviving life on the streets and finally getting a loving family to take care of him and help him get through college.

Willis’ adopted family didn't approve of his fight career, but he felt he owed it to himself and to the 98% of the kids in his situation who don't graduate college to go out there, win his fight and be a positive role model.

On June 27, 2016 Willis fought against Juliano Coutinho at World Series of Fighting 31: Ivanov vs. Copeland.  Willis won the fight by TKO in the 2nd round raising his professional record to 4-1. 

Willis made his UFC debut on July 16, 2017 against British fighter James Mulheron at UFC Fight Night: Nelson vs. Ponzinibbio. He won via unanimous decision.

Willis then faced Allen Crowder at UFC 218 on December 2, 2017. Willis won via knockout.

Wills faced Chase Sherman on April 21, 2018 at UFC Fight Night 128. He won the fight via unanimous decision.

Wills faced Mark Hunt on December 2, 2018 at UFC Fight Night 142. He won the fight via unanimous decision.

Willis is expected to face Curtis Blaydes on March 23, 2019 at UFC Fight Night 148

Willis faced Curtis Blaydes on March 23, 2019 at UFC Fight Night 148. Willis lost the fight via unanimous decision.

On May 24, 2019, it was reported that Willis was released from UFC.

On February 11, 2020, news surfaced that Willis had signed with the Professional Fighters League.

Willis was expected to make his debut against Denis Goltsov at PFL 3 on May 6, 2021, but was removed from the fight prior to weigh-ins.