| Res. | Record | Opponent | Method | Event | Date | Round | Time | Location | Notes |
| Loss | 26–14 (1) | Lyoto Machida | KO (front kick) | UFC 224 | 12 May 2018 | 2 | 1:00 | Rio de Janeiro, Brazil | Belfort announced his retirement after the fight. |
| Win | 26–13 (1) | Nate Marquardt | Decision (unanimous) | UFC 212 | 3 June 2017 | 3 | 5:00 | Rio de Janeiro, Brazil | |
| NC | 25–13 (1) | Kelvin Gastelum | NC (overturned) | UFC Fight Night: Belfort vs. Gastelum | 11 March 2017 | 1 | 3:52 | Fortaleza, Brazil | Originally a TKO (punches) win for Gastelum; overturned after he tested positive for a marijuana metabolite. |
| Loss | 25–13 | Gegard Mousasi | TKO (punches) | UFC 204 | 8 October 2016 | 2 | 2:43 | Manchester, England | |
| Loss | 25–12 | Ronaldo Souza | TKO (punches) | UFC 198 | 14 May 2016 | 1 | 4:38 | Curitiba, Brazil | |
| Win | 25–11 | Dan Henderson | KO (punches) | UFC Fight Night: Belfort vs. Henderson 3 | 7 November 2015 | 1 | 2:07 | São Paulo, Brazil | Performance of the Night. |
| Loss | 24–11 | Chris Weidman | TKO (punches) | UFC 187 | 23 May 2015 | 1 | 2:53 | Las Vegas, Nevada, United States | For the UFC Middleweight Championship. |
| Win | 24–10 | Dan Henderson | KO (head kick) | UFC Fight Night: Belfort vs. Henderson 2 | 9 November 2013 | 1 | 1:17 | Goiânia, Brazil | Light Heavyweight bout. Knockout of the Night. |
| Win | 23–10 | Luke Rockhold | KO (spinning heel kick and punches) | UFC on FX: Belfort vs. Rockhold | 18 May 2013 | 1 | 2:32 | Jaraguá do Sul, Brazil | Knockout of the Night. |
| Win | 22–10 | Michael Bisping | TKO (head kick and punches) | UFC on FX: Belfort vs. Bisping | 19 January 2013 | 2 | 1:27 | São Paulo, Brazil | Return to Middleweight. Knockout of the Night. |
| Loss | 21–10 | Jon Jones | Submission (keylock) | UFC 152 | 22 September 2012 | 4 | 0:54 | Toronto, Ontario, Canada | For the UFC Light Heavyweight Championship. |
| Win | 21–9 | Anthony Johnson | Submission (rear-naked choke) | UFC 142 | 14 January 2012 | 1 | 4:49 | Rio de Janeiro, Brazil | Catchweight (197 lb) bout; Johnson missed weight. |
| Win | 20–9 | Yoshihiro Akiyama | KO (punches) | UFC 133 | 6 August 2011 | 1 | 1:52 | Philadelphia, Pennsylvania, United States | Knockout of the Night. |
| Loss | 19–9 | Anderson Silva | KO (front kick and punches) | UFC 126 | 5 February 2011 | 1 | 3:25 | Las Vegas, Nevada, United States | For the UFC Middleweight Championship. |
| Win | 19–8 | Rich Franklin | TKO (punches) | UFC 103 | 19 September 2009 | 1 | 3:02 | Dallas, Texas, United States | Catchweight (195 lbs) bout. Knockout of the Night. |
| Win | 18–8 | Matt Lindland | KO (punches) | Affliction: Day of Reckoning | 24 January 2009 | 1 | 0:37 | Anaheim, California, United States | |
| Win | 17–8 | Terry Martin | KO (punches) | Affliction: Banned | 19 July 2008 | 2 | 3:12 | Anaheim, California, United States | Middleweight debut. |
| Win | 16–8 | James Zikic | Decision (unanimous) | Cage Rage 23 | 22 September 2007 | 3 | 5:00 | London, England | Won the Cage Rage Light Heavyweight Championship. |
| Win | 15–8 | Ivan Serati | TKO (punches) | Cage Rage 21 | 21 April 2007 | 1 | 3:47 | London, England | |
| Loss | 14–8 | Dan Henderson | Decision (unanimous) | PRIDE 32: The Real Deal | 21 October 2006 | 3 | 5:00 | Las Vegas, Nevada, United States | Belfort tested positive for elevated testosterone. |
| Win | 14–7 | Kazuo Takahashi | KO (punch) | PRIDE: Critical Countdown Absolute | 1 July 2006 | 1 | 0:36 | Saitama, Japan | |
| Loss | 13–7 | Alistair Overeem | Decision (unanimous) | Strikeforce: Revenge | 9 June 2006 | 3 | 5:00 | San Jose, California, United States | Catchweight (210 lbs) bout. |
| Win | 13–6 | Antony Rea | KO (punches) | Cage Rage 14 | 3 December 2005 | 2 | 1:14 | London, England | |
| Loss | 12–6 | Alistair Overeem | Submission (guillotine choke) | PRIDE: Total Elimination 2005 | 23 April 2005 | 1 | 9:36 | Osaka, Japan | |
| Loss | 12–5 | Tito Ortiz | Decision (split) | UFC 51 | 5 February 2005 | 3 | 5:00 | Las Vegas, Nevada, United States | |
| Loss | 12–4 | Randy Couture | TKO (doctor stoppage) | UFC 49 | 21 August 2004 | 3 | 5:00 | Las Vegas, Nevada, United States | Lost the UFC Light Heavyweight Championship. |
| Win | 12–3 | Randy Couture | TKO (doctor stoppage) | UFC 46 | 31 January 2004 | 1 | 0:49 | Las Vegas, Nevada, United States | Won the UFC Light Heavyweight Championship. |
| Win | 11–3 | Marvin Eastman | TKO (knees and punches) | UFC 43 | 6 June 2003 | 1 | 1:07 | Las Vegas, Nevada, United States | |
| Loss | 10–3 | Chuck Liddell | Decision (unanimous) | UFC 37.5 | 22 June 2002 | 3 | 5:00 | Las Vegas, Nevada, United States | Return to Light Heavyweight. |
| Win | 10–2 | Heath Herring | Decision (unanimous) | PRIDE 14: Clash of the Titans | 27 May 2001 | 3 | 5:00 | Yokohama, Japan | |
| Win | 9–2 | Bobby Southworth | Submission (rear-naked choke) | PRIDE 13: Collision Course | 25 March 2001 | 1 | 4:09 | Saitama, Japan | |
| Win | 8–2 | Daijiro Matsui | Decision (unanimous) | PRIDE 10: Return of the Warriors | 27 August 2000 | 2 | 10:00 | Saitama, Japan | |
| Win | 7–2 | Gilbert Yvel | Decision (unanimous) | PRIDE 9: New Blood | 4 June 2000 | 2 | 10:00 | Nagoya, Japan | |
| Loss | 6–2 | Kazushi Sakuraba | Decision (unanimous) | PRIDE 5 | 29 April 1999 | 2 | 10:00 | Nagoya, Japan | Return to Heavyweight. |
| Win | 6–1 | Wanderlei Silva | TKO (punches) | UFC Brazil | 16 October 1998 | 1 | 0:44 | São Paulo, Brazil | Light Heavyweight debut. |
| Win | 5–1 | Joe Charles | Submission (armbar) | UFC Japan | 21 December 1997 | 1 | 4:03 | Yokohama, Japan | |
| Loss | 4–1 | Randy Couture | TKO (punches) | UFC 15 | 17 October 1997 | 1 | 8:16 | Bay St. Louis, Mississippi, United States | UFC Heavyweight title eliminator. |
| Win | 4–0 | Tank Abbott | TKO (punches) | UFC 13 | 30 May 1997 | 1 | 0:52 | Augusta, Georgia, United States | |
| Win | 3–0 | Scott Ferrozzo | TKO (punches) | UFC 12 | 7 February 1997 | 1 | 0:43 | Dothan, Alabama, United States | Won the UFC 12 Heavyweight Tournament. |
| Win | 2–0 | Tra Telligman | TKO (cut) | 1 | 1:17 | UFC 12 Heavyweight Tournament Semifinal. |
| Win | 1–0 | Jon Hess | KO (punches) | SuperBrawl 2 | 11 October 1996 | 1 | 0:12 | Honolulu, Hawaii, United States | |