The 2003–04 AHL season was the 68th season of the American Hockey League. The league introduced the Willie Marshall Award in honor of the career points leader in the AHL, and awards it to the annual top goal scorer.

The AHL switched from a six division alignment to four divisions within two conferences. The Eastern conference consisted of the Atlantic and East divisions, and the Western conference consisted of the North and West divisions. Twenty-eight teams played 80 games each in the schedule. The Milwaukee Admirals finished first overall in the regular season, and won the Calder Cup, defeating the Wilkes-Barre/Scranton Penguins in the finals.

• The Saint John Flames suspend operations, becoming dormant.
• The Hamilton Bulldogs and Quebec Citadelles merger dissolves, remaining as a Montreal Canadiens affiliate.
• The Edmonton Oilers affiliation resumed operations as the Toronto Roadrunners, based in Toronto, Ontario, playing in the North division.
• All teams playing in the 2002-03 North Division (Lowell Lock Monsters, Manchester Monarchs, Portland Pirates, Providence Bruins and Worcester IceCats) play in the new Atlantic Division.
• The Hartford Wolf Pack and Springfield Falcons switch from the 2002-03 East Division to the new Atlantic Division.
• All teams playing in the 2002-03 South Division (Hershey Bears, Norfolk Admirals, Philadelphia Phantoms and Wilkes-Barre/Scranton Penguins) play in the new East Division.
• The Albany River Rats, Binghamton Senators and Bridgeport Sound Tigers continue to play in the (new) East Division.
• The Hamilton Bulldogs, Manitoba Moose and St. John's Maple Leafs switch from the Canadian Division to the new North Division.
• The Cleveland Barons, Rochester Americans and Syracuse Crunch switch from the Central Division to the new North Division.
• All teams playing in the 2002-03 West Division (Chicago Wolves, Houston Aeros, Milwaukee Admirals, San Antonio Rampage and Utah Grizzlies) continue to play in the West Division.
• The Cincinnati Mighty Ducks and Grand Rapids Griffins switch from the Central Division to the new West Division.

Wolf Pack

Monsters

Monarchs

Pirates

Bruins

Falcons

IceCats

Rats

Senators

Tigers

Bears

Admirals

Phantoms

Penguins

Barons

Bulldogs

Moose

Americans

Leafs

Crunch

Road
runners

Wolves

Mighty Ducks

Griffins

Aeros

Admirals

Rampage

Grizzlies

Atlantic Division East Division
North Division West Division

•  y–  indicates team clinched division and a playoff spot
•  x–  indicates team clinched a playoff spot
•  e–  indicates team was eliminated from playoff contention

Note: GP = Games played; G = Goals; A = Assists; Pts = Points; PIM = Penalty minutes