Michael Julian Johnson (born June 4, 1986) is an American professional mixed martial artist. Johnson currently fights in the Lightweight division of the Ultimate Fighting Championship (UFC). A professional since 2008, Johnson mostly competed in his regional circuit, before signing onto the Ultimate Fighting Championship to appear on The Ultimate Fighter: Team GSP vs. Team Koscheck, in which he was the runner-up.

Johnson was born in St. Louis, Missouri, on June 4, 1986. He was raised as the youngest of three siblings. Johnson began fighting at the age of 10, after his father's fatal heart attack. The incident made Johnson want to exert his anger physically. Johnson later said, "I lost something, a huge part of me....Fighting was my way of not dealing with my dad's passing. Now that I think of it, of course, it was the wrong thing to do, especially putting all that burden on my mom having to deal with it." Athletic, Johnson was a three-sport varsity athlete at Marquette High School in Chesterfield, Missouri. Johnson later received a full scholarship to play football at Central Methodist University, but transferred after one year to Meramec Community College, where he was one of the top NJCAA wrestlers in the country.

Johnson is a former Midwest Fight League and Xtreme Cage Fighting Champion who won those titles in July 2008 and October 2009, respectively. Johnson trained at Springfield Fight Club, which is an affiliate of Gracie Barra based in Springfield, Missouri. Johnson also worked there as the assistant mixed martial arts coach.

Johnson then signed onto the Ultimate Fighting Championship circuit to appear on The Ultimate Fighter: Team GSP vs. Team Koscheck.

Johnson's entry into the show was, in part, due to his persistence in attending tryouts for the show. After making the final interview round of The Ultimate Fighter: Team Nogueira vs. Team Mir, Johnson was told that he wasn't the right fit for the show. Johnson then tried out for the ninth season of the show, before finally becoming accepted onto the twelfth season after telling the producers, "I've been getting tired of chasing you [expletive] around the country. I'm here; I'm not going to go anywhere. If you guys don't pick me, I'm going to try out again." Finally, Johnson was signed.

Johnson's first fight took place on the debut episode of the season, where he faced unbeaten Pablo Garza. Johnson scored a unanimous decision victory, which moved him into the house.

In the second episode, both St-Pierre and Koscheck had Johnson at the top of their lists when it came time to select fighters. During the team selection process, however, St-Pierre created a fake list that did not have Johnson among his top selections and subtly showed it to Koscheck to fool him into believing it. This seemed to manipulate Koscheck into picking Marc Stevens, as he may have believed he could take Johnson later. This allowed St-Pierre to choose Johnson with the second overall pick.

Johnson competed in his preliminary round matchup against Aaron Wilkinson in the third episode. After some early striking exchanges in the first round, Wilkinson was able to take Johnson down and utilize ground-and-pound punches and elbows. In the second round, Johnson landed an early superman punch, as well as a takedown. After takedowns were achieved by both men, Johnson stuffed a final attempt and took the second round on the judges' scorecards. In the sudden victory round, Johnson attacked quickly, which allowed him to end the fight via a rear-naked choke.