Cooper was forced to miss last weekend's 2-0 win at Huddersfield Town with a calf strain and the captain also sat out Tuesday night's 2-0 win at home to Hull City.
Whites head coach Marcelo Bielsa then revealed on Thursday that Cooper was in contention to feature against the Bluebirds but that the captain would not be risked unless he was 100 per cent.
But Cooper has failed to make it meaning Gaetano Berardi will again partner Ben White at centre back.
Adam Forshaw (hip), Tyler Roberts (hamstring) and Jamie Shackleton (muscle) also remain out injured.
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Cardiff boss Neil Harris has made three changes to his side with Sean Morrison replacing Curtis Nelson alongside Aden Flint at centre half.
Joe Ralls and Will Vaulks also come into the side for Leandro Bacuna and Junior Hoilett who is injured.
Gary Madine has also failed to recover from a back problem and is replaced by the returning Robert Glatzel on the bench.
Alex Smithies and Gavin Whyte have recovered from illness to take their places on the bench but former Whites captain Sol Bamba is still missing as he recovers from an ACL injury.
Leeds United: Casilla, Ayling, White, Berardi, Dallas, Phillips, Klich, Harrison, Costa, Hernandez, Bamford. Subs: Miazek, Douglas, Struijk, Alioski, Gotts, Clarke, Nketiah.
Cardiff City: Etheridge; Peltier, Morrison, Flint, Bennett; Mendez-Laing, Pack, Vaulks, Ralls, Tomlin; Ward. Subs: Smithies, Bacuna, Glatzel, Murphy, Paterson, Nelson, Whyte.
Referee: Tony Harrington.