Group stage matches began on 21 October 2004 and concluded on 16 December 2004.
The top three teams in each group progressed to the Round of 32, to be joined by the eight third-place finishers from the Champions League group stage.
The group stage draw took place on 5 October 2004.
Pot 1 comprised the top eight clubs in the team ranking.
A team's seeding was determined by the UEFA coefficients.