The year 2013 was the 21st year in the history of the Ultimate Fighting Championship (UFC), a mixed martial arts promotion based in the United States. 2013 started with UFC on FX: Belfort vs. Bisping. 2013 also saw the introduction of the women's bantamweight weight class with UFC 157: Rousey vs. Carmouche.

The following fighters fought their first UFC fight in 2013:

UFC on FX: Belfort vs. Bisping (also known as UFC on FX 7) was a mixed martial arts event held by the Ultimate Fighting Championship on January 19, 2013, at Ginásio do Ibirapuera in São Paulo, Brazil.

The main fight featured middleweights Michael Bisping and Vitor Belfort. The event also held the first UFC fight for Daniel Sarafian, middleweight finalist on the first season of The Ultimate Fighter: Brazil. Sarafian was injured before the championship fight with Cezar Ferreira, who went on to win the show.

Johnny Eduardo was briefly linked to a bout at this event against Iuri Alcântara, but was replaced by George Roop. Roop was then injured and replaced by UFC newcomer Pedro Nobre.

Thiago Perpetuo was expected to face Michael Kuiper at the event; however, Perpetuo suffered an injury and was replaced by Caio Magalhaes. On December 27, it was announced that Magalhaes had also pulled out of the bout and that Kuiper would be shifted to UFC on Fox 6 on January 26, 2013 to face Buddy Roberts.

Roger Hollett was expected to face Wagner Prado at the event; however, Hollett was forced out of the bout with a torn bicep and was replaced by promotional newcomer Ildemar Alcântara.

The following fighters received $50,000 bonuses.