Aaron Isaac Rosa (born May 28, 1983) is an American former professional mixed martial artist. A professional competitor from 2005 until 2013, he has competed for the UFC, Bellator, ShoXC, and Strikeforce.

Born and raised in the border-town of Del Rio, Texas, Rosa was a talented football player, competing at Del Rio High School before continuing his career at Angelo State University, where he was also a standout. In January 2004, Rosa began training in mixed martial arts.

Rosa made his amateur debut later that year in 2004 and made his professional debut in November 2005. Rosa compiled an undefeated record of 9–0 fighting on the local circuit before being signed by ShoXC.

Rosa made his promotional debut on July 27, 2007, at ShoXC: Elite Challengers Series against Jefferson Silva and won via TKO. Rosa made his next appearance on October 26, 2007, against Jared Hamman and was handed his first professional defeat via rear-naked choke submission in the second round. Rosa then faced Jaime Fletcher on March 21, 2008, and was defeated again, via unanimous decision.

Rosa was scheduled to fight Seth Petruzelli, at EliteXC: Heat, but Petruzelli was moved to the main event to fight Kevin "Kimbo Slice" Ferguson after Ken Shamrock had to pull out due to an injury.

After picking up a win under the Adrenaline MMA banner, Rosa made his Strikeforce debut at Strikeforce Challengers: Evangelista vs. Aina on May 15, 2009, in a Light Heavyweight bout against Anthony Ruiz. Rosa won via rear-naked choke submission in the first round. Rosa made his next appearance on November 20, 2009, at Strikeforce Challengers: Woodley vs. Bears against Rafael Cavalcante. Rosa was defeated in the second round via TKO.

At Bellator 20 he defeated veteran Robert Villegas by unanimous decision. Rosa then defeated The Ultimate Fighter 10 alumnus Abe Wagner via submission at Titan FC 17: Lashley vs. Ott.

On May 13, 2011, it was announced that Rosa had signed with the UFC.