Irish U-21 National Championships - Dublin - October 10-17 2003
Preliminaries
| 2003-10-10 | 69kg | Roy Sheahan | Ross Browning | WO. |
| 2003-10-10 | 69kg | Anthony Fitzgerald | Stephen Davitt | 15:14 |
| 2003-10-10 | 69kg | Stephen Boyle | Hugh Nevin | WO. |
| 2003-10-10 | 69kg | Derek Murtagh | Chris McHale Roe | 19:6 |
| 2003-10-10 | 69kg | Ciaran Curtis | Gary McCafferty | RSC 1 |
| 2003-10-10 | 69kg | Jimmy Sweeney | Daniel Quinn | 15:11 |
| 2003-10-10 | 69kg | Ryan Greene | Thomas Walsh | 16:7 |
Quarterfinals
| 2003-10-10 | 60kg | John Quinn | Barry Gillespie | 20:7 |
| 2003-10-10 | 60kg | Garreth Dunne | Aaron Sadlier | 18:13 |
| 2003-10-10 | 60kg | John Lyons | Niall Murray | 19:9 |
| 2003-10-10 | 64kg | John Joe McDonagh | Peter Taylor | 10:2 |
| 2003-10-10 | 69kg | Anthony Fitzgerald | Stephen Boyle | 17:7 |
| 2003-10-10 | 69kg | Ciaran Curtis | Derek Murtagh | 18:6 |
| 2003-10-10 | 69kg | Jimmy Sweeney | Ryan Greene | 10:8 |
| 2003-10-10 | 69kg | Roy Sheahan | John Joe Nevin | 14:1 |
| 2003-10-10 | 81kg | John Sweeney | Michael Stokes | AB 2 |
| 2003-10-10 | 81kg | Michael McDonagh | Paul Hickey | KO 4 |
| 2003-10-10 | 91kg | William Byrne | Joe Walsh | 15:6 |
Semifinals
| 2003-10-11 | 51kg | Thomas Lee | Noel Muldowney | AB 3 |
| 2003-10-11 | 51kg | Derek Thorpe | Derek McArdle | WO. |
| 2003-10-11 | 54kg | Anthony Hopkins | James Linden | 12:6 |
| 2003-10-11 | 57kg | Francis Linden | Thomas McHale Roe | RSC 1 |
| 2003-10-11 | 57kg | David Joyce | Alan Siberry | RSC 2 |
| 2003-10-11 | 60kg | Thomas Dwyer | John Quinn | 14:9 |
| 2003-10-11 | 60kg | Garreth Dunne | John Lyons | 24:3 |
| 2003-10-11 | 64kg | Michael McLaughlin | Barry Muldoon | 23:6 |
| 2003-10-11 | 64kg | John Joe McDonagh | William McLaughlin | 16:7 |
| 2003-10-11 | 69kg | Roy Sheahan | Anthony Fitzgerald | RSCO 3 |
| 2003-10-11 | 69kg | Jimmy Sweeney | Ciaran Curtis | 13:9 |
| 2003-10-11 | 81kg | Darren O'Neill | Abdul Hussain | 21:4 |
| 2003-10-11 | 81kg | Michael McDonagh | John Sweeney | 8:5 |
| 2003-10-11 | 91kg | Patrick Coyle | Darren O'Toole | 16:6 |
| 2003-10-11 | 91kg | Shane Curran | William Byrne | 13:7 |
Finals
| 2003-10-17 | 48kg | Conor Ahern | --- | WO. |
| 2003-10-17 | 51kg | Thomas Lee | Derek Thorpe | RSC 3 |
| 2003-10-17 | 54kg | Eric Donovan | Anthony Hopkins | RSC 1 |
| 2003-10-17 | 57kg | David Joyce | Francis Linden | AB 4 |
| 2003-10-17 | 60kg | Garreth Dunne | Thomas Dwyer | 29:4 |
| 2003-10-17 | 64kg | John Joe McDonagh | Michael McLaughlin | 12:4 |
| 2003-10-17 | 69kg | Roy Sheahan | Jimmy Sweeney | 15:3 |
| 2003-10-17 | 75kg | Robert Long | Sean Shevlin | 37:21 |
| 2003-10-17 | 81kg | Darren O'Neill | Michael McDonagh | 12:4 |
| 2003-10-17 | 91kg | Patrick Coyle | Shane Curran | 6:4 |