| Season: | 2004 |
| Num Teams: | 16 |
| Winners: | Montreal Impact (2nd title) |
| Premiers: | Portland Timbers (1st title) |
| League Topscorer: | Dante Washington, Alan Gordon (17 goals) |
| Nextseason: | 2005 USL-1 |
The 2004 USL A-League was an American Division II league run by the United Soccer League during the summer of 2004.
The Syracuse Salty Dogs advance, 5–4, on penalty kicks after the series ended tied 2–2 on aggregate.
The Montreal Impact advance 2–0 on aggregate.
The Seattle Sounders advance 3–2 on aggregate.
The Vancouver Whitecaps advance 3–0 on aggregate.
The Montreal Impact advanced 3–1 on aggregate.
The Seattle Sounders advance 2–1 on aggregate.
MVP: Mauricio Vincello
| Rank | Scorer | Club | GP | Goals | Assists | Points |
|---|---|---|---|---|---|---|
| 1 | Virginia Beach Mariners | 27 | 17 | 6 | 40 | |
| 2 | Byron Alvarez | Portland Timber | 25 | 16 | 4 | 36 |
| 3 | Alan Gordon | Portland Timbers | 27 | 17 | 1 | 35 |
| 4 | Ali Gerba | Toronto Lynx | 25 | 15 | 4 | 34 |
| 5 | Johnny Torres | Milwaukee Wave United | 26 | 11 | 7 | 29 |
| 6 | Mac Cozier | 28 | 12 | 4 | 28 | |
| 7 | Greg Howes | 24 | 9 | 8 | 26 | |
| 8 | Todd Dusosky | 23 | 10 | 4 | 24 | |
| McColm Cephas | Richmond Kickers | 26 | 10 | 4 | 24 | |
| Chris Carrieri | Rochester Rhinos | 27 | 8 | 8 | 24 | |
| 11 | Mauricio Salles | Puerto Rico Islanders | 25 | 11 | 1 | 23 |
| 12 | Jason Jordan | Vancouver Whitecaps | 19 | 7 | 7 | 21 |
| 13 | Welton Melo | Seattle Sounders | 23 | 5 | 10 | 20 |
| Hugo Alcaraz-Cuellar | Portland Timber | 26 | 5 | 10 | 20 | |
| Matthew Delicâte | Richmond Kickers | 26 | 7 | 6 | 20 |
All A-League First Team
F: Byron Alvarez (Portland Timbers); Alan Gordon (Portland Timbers) (Co-Leading Goalscorer); Dante Washington (Virginia Beach Mariners) (Co-Leading Goalscorer)
M: Mauro Biello (Montreal Impact); Sandro Grande (Montreal Impact); Alex Pineda Chacón (Atlanta Silverbacks); Johnny Torres (Milwaukee Wave United)
D: Gabriel Gervais (Montreal Impact) (Defender of the Year); Dustin Branan (Minnesota Thunder); Peter Luzak (Richmond Kickers)
G: Greg Sutton (Montreal Impact) (MVP & Goalkeeper of the Year)
Coach: Bobby Howe Portland Timbers) (Coach of the Year)
All A-League Second Team
F: Mac Cozier (Atlanta Silverbacks); Ali Gerba (Toronto Lynx); Greg Howes (Milwaukee Wave United)
M: Hugo Alcaraz-Cuellar Portland Timbers); Justin Evans (Charleston Battery); Alfredo Valente (Vancouver Whitecaps); Richie Williams (Richmond Kickers)
D: Craig Demmin (Rochester Raging Rhinos); Nevio Pizzolitto (Montreal Impact); Mark Watson (Charleston Battery)
G: Joe Warren (Minnesota Thunder)