The 2004 European Junior Swimming Championships were held from 15 to 18 July 2004 in Lisbon, Portugal.
Medal summary Boy's events
| 50 m freestyle
| 100 m freestyle
| 200 m freestyle CR
| 400 m freestyle
| 1500 m freestyle
| 50 m backstroke
| 100 m backstroke
| 200 m backstroke
| 50 m breaststroke
| 100 m breaststroke
| 200 m breaststroke
| 50 m butterfly
| 100 m butterfly
| 200 m butterfly
| 200 m individual medley
| 400 m individual medley
| freestyle relay
| freestyle relay
| medley relay
Girl's events
| 50 m freestyle
| 100 m freestyle
| 200 m freestyle CR
| 400 m freestyle
| 800 m freestyle
| 50 m backstroke
| 100 m backstroke
| 200 m backstroke
| 50 m breaststroke
| 100 m breaststroke
| 200 m breaststroke
| 50 m butterfly
| 100 m butterfly
| 200 m butterfly CR
| 200 m individual medley
| 400 m individual medley
| freestyle relay
| freestyle relay
| medley relay