Sam Saunders continued his “get out of jail free” form with a last minute penalty that saw the Bees rise to second in the table.
The Gentry came to Griffin Park on the back of their first away win but there was never really much danger of the away side causing any damage to Brentford on Saturday.
The Bees bombarded the Preston goal in the first half, with Declan Rudd being the far busier of the goalkeepers throughout the game.
He saved well from Clayton Donaldson and saved well from a Sam Saunders strike.
Donaldson then had a blistering shot well saved before Toumani Diagouraga smashed the ball wide from just inside the area.
This theme continued throughout the first half with Tom Adeyemi running the show – the on-loan Norwich man’s powerful runs proved difficult for the Preston defence to handle.
Harlee Dean came closest to breaking the deadlock in the first half when he put his head on a Saunders corner, only for it to be cleared off the line by the man on the post.
The second half was more nervy as Preston looked to find a way back into the game and it seemed like it would be another one of those frustrating days for Brentford.
Marcello Trotta was introduced late in the second half and he could have put Brentford in the lead, but he failed to connect with a Shaleum Logan cross.
Saunders then had his freekick rattle the crossbar before the deciding factor came in the 93rd minute of play. Logan launched the ball into the Preston area for Dean to head down for Saunders, who ran into the box before he was bundled down by two Preston players.
After what seemed like a lifetime Saunders rifled the penalty into the back of the net to make sure Brentford took advantage of Sheffield United’s slip up.
The Bees now play Sheffield United on Saturday in a 12.45 kick off and BIAS and the club have organised free away travel for visiting fans.