Tyler Jeffrey Dillashaw (born February 7, 1986) is an American former professional mixed martial artist who competed in the Ultimate Fighting Championship (UFC), where he is a former two-time UFC Bantamweight Champion.
Dillashaw competed on the 2011 Ultimate Fighter season. In 2014, he won the UFC Bantamweight Championship by dethroning Renan Barão, who was on a 32-fight unbeaten streak. Dillashaw lost the title to Dominick Cruz by split decision in 2016 before regaining it against Cody Garbrandt in 2017. He was later stripped of the belt in 2019 after testing positive for a banned substance, erythropoietin, in the drug tests for his UFC Flyweight Championship bout against Henry Cejudo. He received a two-year suspension and made his comeback in 2021, challenging for the bantamweight championship again in 2022 before retiring.