Cardiff defender Ben Turner and striker Kenwyne Jones are among five players released by the club.
Centre-half Turner, who has spent five years at Cardiff, Jones, Joe Lewis, Etien Velikonja and Filip Kiss will not be offered new contracts.
Turner joined the Bluebirds in August 2011 and scored a 120th-minute equaliser against Liverpool in the 2012 League Cup final, which the Welsh club went on to lose 3-2 on penalties.
Former Sunderland forward Jones, who arrived from Stoke in a swap deal that saw Peter Odemwingie move in the opposite direction in January 2014, scored 19 goals in 67 appearances for Cardiff.
Cardiff have also released under-21s players Jazzi Barnum-Bobb, Abdi Noor, Tyler Roche and Curtis Watkins.