UFC Fight Night: Belfort vs. Gastelum (also known as UFC Fight Night 106) was a mixed martial arts event produced by the Ultimate Fighting Championship held on March 11, 2017, at the Centro de Formação Olímpica do Nordeste in Fortaleza, Brazil.

The event was the second that the promotion has hosted in Ceará, and first since UFC on Fuel TV: Nogueira vs. Werdum which was held at Ginásio Paulo Sarasate in June 2013. This event was expected to be UFC Fight Night 107, but an initially planned UFN 106 in Las Vegas, Nevada never materialized, prompting the change in numbers.

A middleweight bout between former UFC Light Heavyweight Champion and UFC 12 Heavyweight Tournament winner Vitor Belfort and The Ultimate Fighter: Team Jones vs. Team Sonnen middleweight winner Kelvin Gastelum was the event headliner.

Ion Cuțelaba was briefly linked to a bout against Henrique da Silva at the event. However the bout never materialized due to an undisclosed injury for Cuțelaba. da Silva was expected to remain on the card against another opponent, but elected to take another fight at a separate event.

Alex Nicholson was briefly linked to a bout with promotional newcomer Paulo Costa at the event. However, Nicholson was removed from the pairing in favor of Garreth McLellan.

Max Griffin was expected to face Sérgio Moraes at the event. However, Griffin pulled out of the fight on March 2 citing an undisclosed injury. He was replaced by promotional newcomer Davi Ramos.

Godofredo Pepey and Kyle Bochniak were expected to face each other at the event. However, both fighters pulled out of the fight during the week leading up to the event citing injuries and the bout was scrapped.

The following fighters were awarded $50,000 bonuses: