Since turning professional in 2006, Cariaso has competed in several organizations, obtaining wins in large MMA promotions such as Strikeforce and EliteXC, with all of his fights taking place in his native Northern California.
On October 28, 2010, World Extreme Cagefighting merged with the Ultimate Fighting Championship. As part of the merger, all WEC fighters were transferred to the UFC. In his first UFC fight, Cariaso faced Will Campuzano on January 22, 2011 at UFC Fight Night 23. He won the fight via unanimous decision. Cariaso was expected to face Norifumi Yamamoto on May 28, 2011 at UFC 130. However, Yamamoto was forced out of the bout with an injury and replaced by Michael McDonald. Cariaso lost a hard fought split decision to McDonald in a closely contested fight. Cariaso faced UFC newcomer Vaughan Lee on November 5, 2011 at UFC 138. He won the fight via split decision. Cariaso faced Takeya Mizugaki on February 26, 2012 at UFC 144. Cariaso defeated Mizugaki via unanimous decision. Cariaso decided to drop to the flyweight division where he faced Josh Ferguson at. He won the fight via unanimous decision. Cariaso fought John Moraga on December 29, 2012 at UFC 155. He was submitted in the third round with a guillotine choke. Cariaso faced Jussier Formiga on May 18, 2013 at UFC on FX 8. He lost the fight via unanimous decision. Cariaso next faced Iliarde Santos on October 9, 2013 at UFC Fight Night 29. He won the fight via TKO in the second round. Cariaso was expected to face Kyoji Horiguchi on February 1, 2014 at UFC 169. However, Horoguchi pulled out of the bout citing injury and was replaced by WEC veteran Danny Martinez. Cariaso won the fight via unanimous decision. Cariaso faced Louis Smolka on May 10, 2014 at UFC Fight Night 40. He won the fight via split decision. A rescheduled bout with Kyoji Horiguchi was expected to take place on September 20, 2014 at UFC Fight Night 52. However, on July 15, 2014 it was announced that Cariaso would receive a title shot against UFC Flyweight champion Demetrious Johnson in the co-main event of UFC 177. On August 12, the Johnson/Cariaso bout was moved to the main event of UFC 178. Cariaso lost the bout via submission due to a kimura in the second round. Cariaso faced Henry Cejudo on March 14, 2015 at UFC 185. He lost the fight by unanimous decision. Cariaso faced Sergio Pettis on October 3, 2015 at UFC 192. He lost the fight via unanimous decision. On February 2, 2016, Cariaso announced that he is retiring from active competition.
