Steven Timothy Peterson (born May 29, 1990) is an American former professional mixed martial artist. Peterson competed in the Featherweight division, for the Ultimate Fighting Championship (UFC). A professional competitor, from 2010 to 2023, Peterson has also competed for Bellator Fighting Championships, and the Legacy Fighting Alliance.

Peterson made his Bellator Fighting Championships debut, on September 2, 2010 at Bellator 27, against Ernest de la Cruz, winning by unanimous decision.

Peterson made his second and final appearance in Bellator, on March 23, 2012, against Chris Jones, at Bellator 62, losing by split decision. Peterson competed extensively in both Legacy FC and Legacy Fighting Alliance, winning the Legacy FC Bantamweight title, at Legacy FC 56 vs. Manny Vasquez by rear-naked choke. Peterson lost a title unification bout at LFA 1, against Leandro Higo by unanimous decision.

Peterson competed on Dana White's Contender Series 7, for a chance at a UFC contract, on August 22, 2017, against Benito Lopez, losing by split decision.

Peterson was expected to make his UFC debut, at UFC Fight Night 126, on February 18, 2018, against Humberto Bandenay. However, due to visa issues, for Bandenay, he was replaced by Brandon Davis. Peterson lost the fight by unanimous decision. This fight earned Peterson the Fight of the Night award.

Peterson's next bout took place, at The Ultimate Fighter: Undefeated Finale, on July 6, 2018, against Matt Bessette. Peterson won the fight by split decision.

Peterson faced Luis Peña, on March 23, 2019, at UFC Fight Night 148. At the weigh-ins, Peña weighed in at 148.5 lbs, 2.5 pounds over the featherweight non-title fight limit of 146 lbs. Peña was fined 30% of his fight purse, and the bout proceed at a catchweight. Peterson lost the fight by unanimous decision. Peterson signed a new, four-fight contract with the UFC after the fight.

Peterson faced Alex Caceres, on July 20, 2019, at UFC on ESPN 4. Peterson lost the fight by unanimous decision.