Mark Warburton's Brentford side lead Reading 1-0 at half time thanks to Alan Judge's goal just seven minutes into the game.
Gareth McCleary's dipping effort was well held by David Button inside the opening minutes, with Nathaniel Chalobah then lashing another effort from range over the top of goal.
Needing a win to keep their playoff hopes alive, Brentford made much of the early running, and were ahead when Judge volleyed home at the near post from Andre Gray's cross.
Reading responded well to going a goal behind though and nearly restored parity twice in quick succession. Chalobah glanced Chris Gunter's cross narrowly wide before McCleary blasted another Gunter cross high over the bar.
Alex Pearce then nodded an Oliver Norwood corner narrowly wide of goal, before Alex Pritchard's low strike just before half time deflected agonisingly wide as somehow the scores were not added to.