The 2003 Cheltenham Gold Cup was a horse race which took place at Cheltenham on Thursday 13 March 2003. It was the 75th running of the Cheltenham Gold Cup, and it was won by the pre-race favourite Best Mate. The winner was ridden by Jim Culloty and trained by Henrietta Knight.
Best Mate became the first horse to win consecutive runnings of the Gold Cup since L'Escargot in 1970 and 1971.
| * | Horse | Age | Jockey | Trainer † | SP | |
| 1 | Best Mate | 8 | Jim Culloty | Henrietta Knight | 13/8 fav | |
| 2 | 10 | Truckers Tavern | 8 | Davy Russell | Ferdy Murphy | 33/1 |
| 3 | 2½ | Harbour Pilot | 8 | Paul Carberry | Noel Meade (IRE) | 40/1 |
| 4 | nk | Valley Henry | 8 | Barry Geraghty | Paul Nicholls | 14/1 |
| 5 | 1½ | Behrajan | 8 | Richard Johnson | Henry Daly | 14/1 |
| 6 | 1½ | Commanche Court | 10 | Ruby Walsh | Ted Walsh (IRE) | 8/1 |
| 7 | 4 | Chives | 8 | Richard Guest | Henrietta Knight | 25/1 |
| 8 | 17 | See More Business | 13 | Joe Tizzard | Paul Nicholls | 16/1 |
| 9 | ¾ | You're Agoodun | 11 | Tony McCoy | Martin Pipe | 50/1 |
| 10 | 12 | Colonel Braxton | 8 | Kieran Kelly | Dessie Hughes (IRE) | 33/1 |
| 11 | 10 | Marlborough | 11 | Mick Fitzgerald | Nicky Henderson | 20/1 |
| 12 | 10 | Modulor | 11 | Rodi Greene | Martin Pipe | 200/1 |
| PU | Fence 21 | Hussard Collonges | 8 | Russ Garritty | Peter Beaumont | 8/1 |
| PU | Fence 20 | First Gold | 10 | Thierry Doumen | François Doumen (FR) | 33/1 |
| Fell | Fence 3 | Beef Or Salmon | 7 | Timmy Murphy | Michael Hourigan (IRE) | 5/1 |
* The distances between the horses are shown in lengths or shorter. nk = neck; PU = pulled-up.
† Trainers are based in Great Britain unless indicated.
Further details of the winner, Best Mate:
