Jamaican international Jobi McAnuff delivered the goal that sent Leeds to their first league defeat in 11 matches and gave Palace a thoroughly deserved victory.
The Leeds defence paid a heavy price for backing off striker Andy Johnson as he made a strong run through the middle before passing to McAnuff who beat Neil Sullivan from eight yards out two minutes before the interval.
It was McAnuff who scored a consolation goal in Palace's 2-1 defeat against Leeds earlier this month and he was determined to take his revenge for that result.
Leeds manager Kevin Blackwell promoted David Healy from the bench at the expense of Robbie Blake and included former Wealdstone striker Jermaine Beckford among the substitutes for the first time.
Beckford was thrown into the action for his debut on 77 minutes in a last throw of the dice - defender Stephen Crainey making way - and the eager youngster showed glimpses of his pace.
Palace, undefeated away from home in the league since losing at Plymouth in December, had Michael Hughes back after injury and he reinforced the midfield.
Johnson should have swooped twice in the first 10 minutes but first Sullivan used his legs to save a side-footed shot and then Johnson dragged an angled effort wide of the far post.
The game was played at a high tempo and Leeds' veteran right-back Gary Kelly had a goal-bound half-volley brilliantly finger-tipped around the post by Gabor Kiraly.
Palace looked sharp and dangerous every time they ran at the Leeds defence and Sullivan again rescued his side by parrying Mikele Leigertwood's speculative shot and Fitz Hall somehow failed to bundle in the rebound from a yard out.
McAnuff's goal was simplicity itself and Leeds were desperate to hit back in the second half.
Blake replaced Healy in the 62nd minute and five minutes later the unmarked Matthew Kilgallon headed straight at Kiraly from eight yards and that was as close as Leeds were to come.