Clinton Morrison and Jobi McAnuff gave Palace a two-goal half-time lead before substitute Paul Furlong pulled one back after the break, but QPR were not to come away with a point.
The Eagles made the perfect start with Morrison on target after only three minutes. Mikele Leigertwood hit long over to the far side of the penalty area for skipper Darren Ward to head back into the goalmouth and Morrison reacted swiftly to hook the ball past Paul Jones for his ninth goal of the season.
Rangers came close to levelling when Marc Nygaard's snap shot whistled wide of Gabor Kiraly's post, but Palace were mainly in control.
Ward headed over from Gary Borrowdale's cross and then Wayne Andrews unleashed a real piledriver that flew over the crossbar.
Rangers were gradually coming into it as Scott Donnelly placed his shot wide from 15 yards out before Palace delivered a huge blow to them as McAnuff doubled their lead on 32 minutes.
Dougie Freedman did well to keep the ball in play before surging into the penalty box and feeding McAnuff, who from 15 yards out sweetly drove low giving Jones no chance.
Rangers came out with all guns blazing after the break. Nygaard saw his shot deflected and spin wide of the post and Steve Lomas, who was covering every blade of grass on the pitch, also had a useful chance that drifted past Kiraly's goal.
Waddock's outfit were having a good spell and Furlong gave them hope as he swooped low to rocket his header into the corner of the net following Donnelly's cross from the right.
Rangers kept plugging away, forcing Palace to defend deep and desperately at times.
Still Palace were menacing on the break and Freedman and Morrison both missed glorious chances with only Jones to beat.
Rangers nearly levelled 14 minutes from the end when Kiraly punched Lee Cook's corner on to his crossbar and a few minutes later Furlong came close with another good effort, but Palace held out for the three points.