Sean O'Malley (18-3, 13) was born in Helena, Montana, U.S. on October 24, 1994. At the age of 20 years on March 6, 2015, he made his professional MMA debut against Josh Reyes, winning the fight via 1st-round TKO.
On March 3, 2018, 23-year old Sean O'Malley made his UFC debut on his 10th professional MMA fight at UFC 222 against a 29-year old Andre Soukhamthath, winning the fight via 3-round unanimous decision.
He became the UFC bantamweight champion on August 19, 2023 at age 28 on his 19th professional MMA fight at UFC 292 after defeating a 34-year old Aljamain Sterling via 2nd-round TKO.
O'Malley's last fight was a bantamweight title fight against Merab Dvalishvili for Dvalishvili's UFC Championship title on June 7, 2025. He lost the fight via 3rd-round submission. He is on a 2-fight losing streak.
He has fought 13 times in the UFC, and has a record of 9 wins, 3 losses and 1 no-contest in the promotion.
Some of Sean O'Malley's best fights have been against Aljamain Sterling, Marlon Vera, Eddie Wineland, Raulian Paiva, Thomas Almeida, José Alberto Quiñónez and Kris Moutinho.
O'Malley has 3 losses on his MMA record.
| # | Date | Opponent | Promotion | Weight | Round | Method | Result |
|---|---|---|---|---|---|---|---|
22  | Jun 7, 2025 30 years, 7 months 18-3 (13) | 34 years, 4 months 19-4 (4) | UFC | BT | 3 | SUB | LOSS North-south choke For UFC bantamweight title |
21 | Sep 14, 2024 29 years, 10 months 18-2 (13) | 33 years, 8 months 17-4 (4) | UFC | BT | 5 | UD | LOSS Lost UFC bantamweight title |
20  | Mar 9, 2024 29 years, 4 months 18-1 (13) | 31 years, 3 months 23-8-1 (18) | UFC | BT | 5 | UD | WIN Defended UFC bantamweight title |
19  | Aug 19, 2023 28 years, 9 months 17-1 (13) | 34 years 23-3 (11) | UFC | BT | 2 | TKO | WIN Punches Won UFC bantamweight title |
18  | Oct 22, 2022 27 years, 11 months 16-1 (12) | 29 years, 8 months 16-3 (8) | UFC | BT | 3 | SD | WIN |
17  | Jul 2, 2022 27 years, 8 months 15-1 (12) | 35 years, 9 months 19-7 (13) | UFC | BT | 2 | NC | NC Accidental eye poke |
16  | Dec 11, 2021 27 years, 1 months 15-1 (12) | 26 years, 1 months 21-3 (7) | UFC | BT | 1 | TKO | WIN Punches |
15 | Jul 10, 2021 26 years, 8 months 14-1 (11) | Kris Moutinho | UFC | BT | 3 | TKO | WIN Punches |
14  | Mar 27, 2021 26 years, 5 months 13-1 (10) | 29 years, 7 months 22-4 (21) | UFC | BT | 3 | KO | WIN Punch |
13 | Aug 15, 2020 25 years, 9 months 12-1 (9) | 27 years, 8 months 17-6-1 (15) | UFC | BT | 1 | TKO | LOSS Elbows and punches |
12  | Jun 6, 2020 25 years, 7 months 12-0 (9) | 35 years, 11 months 24-13-1 (19) | UFC | BT | 1 | KO | WIN Punch |
11 | Mar 7, 2020 25 years, 4 months 11-0 (8) | José Alberto Quiñónez | UFC | BT | 1 | TKO | WIN Head kick and punches |
10  | Mar 3, 2018 23 years, 4 months 10-0 (7) | 29 years, 4 months 12-5 (11) | UFC | BT | 3 | UD | WIN |
9  | Dec 1, 2017 23 years, 1 months 9-0 (7) | 31 years, 8 months 17-6 (9) | TUF | BT | 3 | UD | WIN |
8 | Jul 18, 2017 22 years, 8 months 8-0 (7) | Alfred Khashakyan | BT | 1 | KO | WIN Punch | |
7 | May 5, 2017 22 years, 6 months 7-0 (6) | David Nuzzo | BT | 1 | KO | WIN Spinning wheel kick | |
6 | Mar 18, 2017 22 years, 4 months 6-0 (5) | Irvin Veloz | BT | 1 | KO | WIN Punch | |
5 | Oct 21, 2016 21 years, 11 months 5-0 (4) | Tycen Lynn | BT | 2 | KO | WIN Head kick | |
4 | Nov 7, 2015 21 years 4-0 (3) | Mark Coates | FL | 3 | UD | WIN | |
3 | Aug 21, 2015 20 years, 9 months 3-0 (3) | Omar Avelar | BT | 1 | SUB | WIN Rear-naked choke | |
2 | Jul 3, 2015 20 years, 8 months 2-0 (2) | Shane Sargent | BT | 1 | KO | WIN Punch | |
1 | Mar 6, 2015 20 years, 4 months 1-0 (1) | Josh Reyes | BT | 1 | TKO | WIN Punches |
