Half-time: QPR 2 Birmingham City 0
Tjaronn Chery’s well taken goal and Junior Hoilett’s penalty put QPR in a commanding position at Loftus Road.
Chery, recalled to the starting line-up by boss Jimmy Floyd Hasselbaink, struck 10 minutes before half-time – his sixth goal of the season and second in three matches.
James Perch pulled the ball back from the left and Chery showed great composure to steady himself and fire low into the far corner.
And Hoilett doubled the lead from the spot four minutes later after Sebastian Polter had been brought down by Michael Morrison.
Polter, preferred to Conor Washington up front, turned away from Paul Robinson and Morrison was arguably fortunate to escape with just a yellow card after bringing down the German as he was about to shoot.
Earlier, Chery’s deflected shot flashed narrowly wide and Birmingham’s David Cotterill fired wide after being picked out by Jacques Mahoma.
Subs: Ingram, El Khayati, Konchesky, Tozser, Washington, Petrasso, Faurlin.