The tournament organisers have tended to wait until much later in the season to name the venue for the final of the second-tier competition, but the decision means the Welsh capital will now host both European finals this season, with the Millennium Stadium having already been confirmed as the venue for the Heineken Cup final.
Cardiff City Stadium, the home of defending Challenge Cup winners Cardiff Blues, has a capacity of 26,828 and becomes the first Welsh ground to host the fixture. The Millennium Stadium has already hosted the Heineken Cup final on three previous occasions.
"Traditionally, we have waited until much closer to the date before selecting the stadium for the Amlin Challenge Cup final," said ERC chief executive Derek McGrath."
The decision could further benefit fans as ERC also confirmed that those supporters who have purchased tickets for the Heineken Cup final will be able to buy Amlin Challenge Cup final tickets at a discount.