Jeffrey 'Jeff' "The Snowman" Monson (born January 18, 1971) is a mixed martial arts fighter from Olympia, Washington. He is affiliated with American Top Team which is based in Coconut Creek, Florida.

After 14 straight victories Monson returned to the UFC. At UFC 57 Monson submitted Branden Lee Hinkle by North South Choke in the first round. At UFC 59 Monson fought his long time hated rival ADCC veteran and Jiu Jitsu black belt Marcio Cruz, Monson won by decision after 3 rounds. At UFC 61 Monson fought BJJ black belt Anthony Perosh, Monson won by tko in the first round.

On November 18, 2006 at UFC 65, Monson fought Tim Sylvia for the UFC heavyweight championship. Monson lost a five round decision and would later ask to be relinquished from his UFC contract in hopes of facing PRIDE heavyweight champion Fedor Emelianenko at a BodogFIGHT scheduled for March 2007. However, negotiations fell through and the match never came to fruition.

At PRIDE 34, on April 8, 2007, Monson defeated Kazuyuki Fujita by rear naked choke at 6:37 of the opening round.

His next fight was scheduled to be against Chris Guillen on August 17, 2007 for the Global Fighting Championships' heavyweight title, but the event was canceled after four of the eight scheduled bouts were removed from the card. He lost the fight against Pedro Rizzo at Art of War 3 which was held on September 1, 2007. During the bout, Monson displayed a much improved level of striking, and kept the fight standing virtually the entire time.

On September 7, 2007, Monson won a total of two matches in the FILA World Championship in Turkey, defeating France's Zoro Piere and Great Britain's Tom Blackledge with submissions. Monson was awarded the 275-pound gold medal when his final opponent Ramon Diaz suffered an injury and was forced to bow out.

Jeff Monson defeated Ricco Rodriguez in the main event of Mixed Fighting Alliance "There Will Be Blood" event on December 13, 2008. He avenged a loss to Rodriguez from almost 7 years prior.