A City home win coupled with Sheffield Wednesday failing to win at Brighton would see the Bluebirds move into the play off places.
Ipswich, Birmingham and Derby, all teams challenging with City and Wednesday for a play off place (Derby still looking at automatic), are all playing away tonight as well so it's imperative that Cardiff capture three points.
Ther are eleven games tonight as most teams play their 36th game of the season.
Leeds beat Cardiff at Elland Rd earliier this season to record a first win over City in decades.
Leeds picked up three points on Saturday when they beat bottom side Bolton but their last away game saw a 4 - 0 hammering at Brighton just over a week ago.
Cardiff will be without Lee Peltier. It was feared the defender had broken his foot when he was substituted 45 minutes into Saturday's 2-0 win at Bristol City but a scan revealed he had suffered only bruising and he is expected to learn in the next 48 hours when he will return.
Sean Morrison replaced him on Saturday and is expected to continue to do so, while Peter Whittingham also returned from a calf strain and though he was substituted with 20 minutes remaining, he is expected to be retained.
Full-back Fabio da Silva remained sidelined with a groin problem but he could also return to contention for Tuesday's fixture.
Leeds striker Chris Wood could return to action but Lewie Coyle is out and head coach Steve Evans also has doubts over Liam Cooper and Souleymane Doukara.
Evans confirmed last week that Wood, who has missed the last seven matches due to a hamstring problem, had targeted a return to contention for the trip to Wales.
Coyle was stretchered off with his left leg heavily strapped during Saturday's 2-1 home win against Bolton and is waiting to learn the full extent of the injury.
Fellow defender Cooper was forced off with a hamstring strain at the weekend and striker Doukara took a knock to a foot. Both players will be assessed, as will defender Scott Wootton (heel).
Referee: Darren Deadman
MATCH FACTS
- Cardiff have won six and lost none of their last eight matches against Leeds on home soil.
- Leeds' win in the reverse fixture was their first in 17 games against the Bluebirds.
- Anthony Pilkington has scored five goals in his last four Championship home games for Cardiff.
- The Whites are winless in their last five away league games (D2 L3).
- Leeds have won more points from losing positions away from home in the Championship this season than any other side (7).