QPR, still without an away win this season, were soundly beaten at Pride Park.
Goals from Matěj Vydra and Tom Lawrence secured victory for Derby, who dominated the second half.
Rangers looked comfortable before conceding in the final seconds of the first half for the second successive game.
They were undone on the counter-attack, with Andreas Weimann beating the offside trap and delivering the ball from the right for Vydra to score from close range.
Worse followed for the visitors when Lawrence netted eight minutes into the second half.
Lawrence drifted in from the left and sent a right-footed shot from the near the edge of the penalty area beyond Alex Smithies.
Keeper Smithies prevented a third Derby goal by producing fines save to deny David Nugent and Lawrence.
Rangers boss Ian Holloway, without the likes of Massimo Luongo and Jordan Cousins, named strikers Idrissa Sylla, Matt Smith and Conor Washington among his substitutes and asked David Wheeler to lead the attack.
Washington and Smith were brought on in the second half.
Smith sent a header over the bar and Washington flicked Luke Freeman’s corner to Jamie Mackie, who was unable to hit the target.
Rangers finally mustered a shot on target in the 90th minute courtesy of Josh Scowen, whose effort was comfortably saved by Scott Carson.
The defeat was QPR’s third in a row.
QPR: Smithies, Baptiste, Lynch (Manning 45), Robinson, Wszolek, Scowen, Ngbakoto (Washington 54), Freeman, Bidwell, Mackie, Wheeler (Smith 64).
Subs not used: Lumley, Petrasso, Chair, Sylla.
This post was last modified on 21/11/2017