LEEDS UNITED found themselves replaced at the top of the Championship table on a night when captain Liam Cooper saw red.
Danish striker Kenneth Zohore ended his eight-game goal drought with a brace and Junior Hoilett added a beauty before Kemar Roofe gave 10-man Leeds hope midway through the second period.
Leeds captain Liam Cooper was sent off at the end of the first half for two bookable offences with Cardiff 2-0 ahead.
The visitors actually played better after the break, but it was not enough to prevent Cardiff boss Neil Warnock from celebrating victory against his former club.
Afterwards, Leeds boss Thomas Christiansen admitted his team had contributed significantly to their own downfall.
“The two mistakes brought Cardiff into the game as they had not created any problems for us, and then the red card was very bad for us,” said Christiansen.
I believe the team responded in the proper way from our defeat at Millwall and we are going to do the same against Sheffield Wednesday.Leeds head coach, Thomas Christiansen.
“There was a good response and good character and we played better with 10 men. I believe the team responded in the proper way from our defeat at Millwall and we are going to do the same against Sheffield Wednesday.”
On Cooper’s red card, Christiansen added: “The player that I was I know that these situations can happen.
“Of course, he is experienced in that situation and he should have known how the ball came.
“But I don’t want to blame anyone individually because we win and lose all together.”
Ezgjan Alioski fired an early warning into the Cardiff side-netting but the contest lacked rhythm as injuries to Pontus Jansson and Stuart Dallas disrupted the flow of the game.
The Leeds pair were able to continue after treatment and Cardiff slowly began to take control with Dallas deflecting Joe Bennett's effort over.
Leeds were undone after 28 minutes when Mateusz Klich slipped and Loic Damour released Hoilett with a cute pass.
Hoilett was travelling at full tilt but he had the presence of mind to find Zohore, who converted his first goal since the opening day of the season.
Cardiff took a firm grip on proceedings after 37 minutes when Kalvin Phillips could only help a long ball on and Hoilett gave Leeds goalkeeper Felix Wiedwald no chance from 20 yards.
Zohore flashed another effort just wide, but Leeds' task was made almost impossible when Cooper was sent off in the third minute of first-half stoppage time.
Cooper had perhaps been fortunate to receive only a caution for his earlier scissors tackle on Damour.
But he saw red after responding sluggishly to a ball played down the touchline and crudely took out Nathaniel Mendez-Laing.
Sean Morrison bundled the ball into the net from the resulting free-kick but the Cardiff captain was flagged offside.
Leeds removed Pablo Hernandez at the break as Matthew Pennington was sent on to cover for the absent Cooper.
The 10 men almost halved the deficit after 54 minutes when Neil Etheridge denied Gaetano Berardi and Alioski with a superb double stop.
The game was seemingly put beyond Leeds five minutes later when Hoilett and Morrison combined and Zohore again tapped home from close range.
Roofe's deflected strike gave Leeds belief they could engineer an unlikely comeback, but the vast majority who made up Cardiff's biggest crowd since April 2016 - 27,160 - went home happy.
Cardiff City: Etheridge, Morrison, Ecuele Manga, Bamba (Halford 90), Peltier, Damour, Bryson, Bennett, Mendez-Laing (Feeney 85), Hoilett, Zohore (Ward 76). Subs Not Used: Tomlin, Connolly, Murphy, Bogle.
Leeds United: Wiedwald, Ayling, Jansson, Cooper, Berardi, Klich (Vieira 67), Phillips, Alioski (Grot 62), Hernandez (Pennington 46), Dallas, Roofe. Subs Not Used: Lonergan, Lasogga, Samuel, Sacko.
Referee: Kevin Friend (Leicestershire).