Warriors can confirm the club's opening game in the competition will be against London Irish and will take place on Sunday, October 5 (kick-off 3pm).
The club complete Pool C with a game against Harlequins on home soil on November 1/2. This fixture date will be confirmed after round one has been played.
The EDF Energy Cup, in its fourth year, will again be contested by the 12 Guinness Premiership clubs and the four Welsh Magners League regions.
Three rounds of matches will be played in the four-team group stages at club grounds before the EDF Energy Cup semi-finals and final which will be held on the weekends of March 28 and April 18.
EDF Energy Cup 08/09:
Group A: Newport Gwent Dragons, Wasps, Gloucester, Newcastle
Group B: Bath, Leicester, Sale, Cardiff
Group C: Ospreys, Warriors, Harlequins, London Irish
Group D: Northampton Saints, Saracens, Bristol, Llanelli