| 2010-03-31 | UFC Fight Night: Florian vs. Gomi | Lightweight | Gleison Tibau def. Caol Uno | TKO (punches) | 1 | 4:13 |
| 2009-11-21 | UFC 106: Ortiz vs. Griffin 2 | Lightweight | Caol Uno vs. Fabricio Camoes | Draw (majority) (29–27, 28–28, 28–28) | 3 | 5:00 |
| 2009-06-13 | UFC 99: The Comeback | Lightweight | Spencer Fisher def. Caol Uno | Decision (unanimous) (29–28, 29–28, 29–28) | 3 | 5:00 |
| 2003-09-26 | UFC 44: Undisputed | Lightweight | Hermes França def. Caol Uno | KO (punch) | 2 | 2:46 |
| 2003-02-28 | UFC 41: Onslaught | Lightweight | B.J. Penn vs. Caol Uno title | Draw (split) (48–46, 47–48, 48–48) | 5 | 5:00 |
| 2002-09-27 | UFC 39: The Warriors Return | Lightweight | Caol Uno def. Din Thomas | Decision (unanimous) (29–27, 29–27, 29–27) | 3 | 5:00 |
| 2002-05-10 | UFC 37: High Impact | Lightweight | Caol Uno def. Yves Edwards | Decision (unanimous) (29–28, 30–29, 29–28) | 3 | 5:00 |
| 2001-11-02 | UFC 34: High Voltage | Lightweight | B.J. Penn def. Caol Uno | KO (punches) | 1 | 0:11 |
| 2001-06-29 | UFC 32: Showdown in the Meadowlands | Lightweight | Caol Uno def. Fabiano Iha | KO (punches) | 1 | 1:48 |
| 2001-02-23 | UFC 30: Battle on the Boardwalk | Lightweight | Jens Pulver def. Caol Uno title | Decision (unanimous) | 5 | 5:00 |