The Oakland Athletics' 2004 season involved the A's finishing 2nd in the American League West with a record of 91 wins and 71 losses.
- October 9, 2003: Marco Scutaro was selected off waivers by the Oakland Athletics from the New York Mets.
- November 18, 2003: Ted Lilly was traded by the Oakland Athletics to the Toronto Blue Jays for Bobby Kielty.
- November 26, 2003: Mark Kotsay was traded by the San Diego Padres to the Oakland Athletics for Terrence Long and Ramon Hernandez.
- December 3, 2003: Wayne Gomes was signed as a Free Agent with the Oakland Athletics.
- February 6, 2004: Eric Karros was signed as a Free Agent with the Oakland Athletics.
- March 15, 2004: Mike Oquist was signed as a Free Agent with the Oakland Athletics.
- April 17, 2004: Kirk Saarloos was traded by the Houston Astros to the Oakland Athletics for Chad Harville.
- August 3, 2004: Eric Karros was released by the Oakland Athletics.
Note: G = Games played; AB = At Bats; H = Hits; Avg. = Batting Average; HR = Home Runs; RBI = Runs Batted In
LEAGUE CHAMPIONS: Sacramento, Modesto
- ^ Marco Scutaro Statistics - Baseball-Reference.com
- ^ Ted Lilly Statistics - Baseball-Reference.com
- ^ http://www.baseball-reference.com/k/kotsama01.shtml
- ^ http://www.baseball-reference.com/g/gomeswa01.shtml
- ^ a b http://www.baseball-reference.com/k/karroer01.shtml
- ^ http://www.baseball-reference.com/o/oquismi01.shtml
- ^ http://www.baseball-reference.com/s/saarlki01.shtml