Palace stretched their unbeaten league run since Neil Warnock returned to the club to four games after seeing off Leicester City at Selhurst.
Two goals in the space of three second-half minutes from Fraizer Campbell and Mile Jedinak was enough to see off the Premier League new-boys and collect the Eagles' second victory in six days to see them continue their climb up the table under the new manager.
The game began in slow fashion but sprang into life in 12 minutes when Julian Speroni was forced into a great diving block to deny Jamie Vardy. Dean Hammond's ball into the box came off Leonardo Ulloa, and Vardy beat Damien Delaney but the Eagles shot-stopper did brilliantly to make himself big and get in the way of his shot before David Nugent put a shot wide.
Then the Eagles ventured forward and after Mile Jedinak's 25-yarder fell straight to Kasper Schmeichel, Fraizer Campbell saw a flicked header flash wide of the mark from Yannick Bolasie's cross.
After an end-to-end opening the chances began to arrive, and the Foxes' top scorer last season Nugent broke forward and dribbled the ball into the final third, but he was forced wide by Delaney and blazed his angled drive over the top.
After those scares, Palace then enjoyed a great spell of domiance, carving out four chances within the space of a couple of minutes. Bolasie's cross from the left was headed back by Jason Puncheon into the path of James McArthur, and after dummying a defender the Scot saw his shot deflected over.
From the resulting corner Puncheon saw a curled shot pushed away by Schmeichel and then when Bolasie had a chance to send the ball back into the box Campbell again was off-target with a header.
Moments later the Eagles went closer again when a Puncheon corner found Joe Ledley at the back post but the Welsh midfielder saw his header cleared over the bar by Esteban Cambiasso.
Late on in the half Vardy did brilliantly to control a fantastic pass by Cambiasso inside the box, and then his cross-shot just evaded Nugent and also the far post as the half ended goalless.
The visitors came out of the traps quickly after the interval and went close again when Vardy found Nugent inside the area and the striker's first-time shot was well blocked by Joel Ward who managed to knock it off-target, and that proved vital as the Eagles took the lead two minutes later.
Puncheon's corner was powerfully met by the head of Scott Dann, and Campbell managed to get the slightest of touches from two yards out to flick the ball past the Foxes defenders on the line and stun Nigel Pearson's side.
With Selhurst rocking the Eagles won a free-kick three minutes later in the left-hand channel, and doubled their lead when another fine Puncheon delivery was met in the air by Jedinak, and he flicked the ball inside the far post to score for the second week in a row.
Warnock threw on the returning Marouane Chamkah with 20 minutes to go and the Morrocan went close with a diving header from a Ward cross which rippled the top of the net but was flagged offside.
Having seen both of his fellow goalscorers from the Everton victory last weekend find the scoresheet once again, Bolasie went close to joining them but saw a stinging drive was caught by Schmeichel as the Eagles saw out the final 10 minutes to continue their fine form.
Palace: Speroni, Ward, Delaney, Dann, Kelly, Jedinak, Ledley, McArthur, Bolasie (Guedioura 90), Puncheon, Campbell (Chamakh 71). Subs: Hennessey, Mariappa, Doyle, Zaha, Gayle.
Leicester: Schmeichel, De Laet (Simpson 64), Konchesky, Drinkwater, Morgan, Hammond (James 69), Vardy, Moore, Cambiasso (Mahrez 64), Ulloa, Nugent. Subs: Hamer, King, Schlupp, Wasilewski.