Jason Parillo (born June 11, 1974, in New York) is an American Mixed Martial Arts (MMA) coach at the RVCA Training Centre and former professional boxer. He is best known for training multiple MMA world champions.

Born in New York in 1974, Parillo was raised in Southern California but still returned to his birthplace each summer until he was 13. Parillo started boxing under Jesse Reid at the age of 16 and started training beginners at 18.^[2] He was 24 when entering the professional ranks, following a brief stint as an amateur with a 21–6 record.^[3] From 1998 to 2003 he was a professional boxer where he obtained an undefeated boxing Record of 8–0 with 6 knockouts. A detached retina brought an abrupt end to his boxing career. Parillo took a two-year break and began to train others full time. ^[3][2][4]

Pat Tenore, founder of RVCA, and friend of Parillo, was sponsoring MMA fighter, B.J. Penn. In 2007, Penn had a rematch against Jens Pulver, a fighter known for his strong boxing, and who used this skill to win their first fight. Tenore introduced the two and Parillo began coaching Penn on boxing. Penn won the rematch against Pulver. Since then Parillo has been training many fighters including former UFC champions, Michael Bisping, Cris Cyborg, Rafael Dos Anjos and Tito Ortiz.^[3][2][4] Parillo is currently Head Coach^[5] based at a BJJ/MMA gym known as The RVCA Sport Training Center. It was built by RVCA founder Pat Tenore (who holds a black belt in Brazilian jiu-jitsu). The training facility was located in Costa Mesa, California.^[6] The training center abruptly closed in September 2023.^[7]

Parillo has twin daughters from a previous marriage.^[2]