It began on 25 March 2009, and ended on 16 September 2009.

All K League clubs excluding participating clubs of the 2009 AFC Champions League entered the group stage.

Clubs ranked odd-numbered places in the 2008 K League were assigned to the Group A, and even-numbered clubs were assigned to the Group B.

The fledgling club Gangwon FC entered the Group A.

The top two clubs of each group qualified for the knockout stage.