Jeff "The Big Frog" Curran (born September 2, 1977) is an American mixed martial artist (MMA). He is currently signed with the Ultimate Fighting Championship (UFC). Curran has also fought for several other notable fighting organizations including: World Extreme Cage Fighting (WEC), PRIDE Fighting Championship, International Fight League (IFL), and King of the Cage (KOTC).

Most recently Curran fought Urijah Faber for the WEC featherweight championship. Curran was defeated by Faber, who retained his title, by submission (guillotine choke) at 4:34 of the second round.

Jeff Curran started his path towards mixed martial arts with Karate and Tae Kwon Do as a child. He began wrestling in the 4th grade and did that until his freshman year when he began Jiu-Jitsu. Jeff also says that as a teen he would box with his grandfather.

Jeff holds a rank of black belt under Professor Pedro Sauer. He is also known as one of the most technical instrustors in the Pedro Sauer Jiu-Jitsu Association. Jeff credits Royce Gracie as being the fighter that made him want to start.

Jeff is president and head instructor of Curran Martial Arts Academy(CMA). He is also owner and promoter of X-treme Fighting Organization. Jeff appeared on the television series Tapout on Versus with fellow Team Curran pro Fighter Matt Flordirosa.