They became the first side to win at Hartlepool this season, but will expect another difficult game when they return for a League One game in ten days.
Reduced to ten men after just eight minutes, Hartlepool had to battle to keep the first half goalless.
But it proved too much for them in the end and now they'll be hoping to put this result behind them in their league campaign.
Full-back Jack Ross was sent off for a professional foul on Steve Hunt, but as he headed for the dressing rooms, he was relieved to see Dimi Konstanopoulos save Hunt's penalty down near his right-hand post.
With the wind behind them, Brentford dominated and Isaiah Rankin hit the home bar with a great 25-yard volley on 28 minutes.
Pools, who had to replace the injured Mark Tinkler on the half-hour, went close when Joel Porter's volley was inches off target.
It took Brentford just three minutes of the second half to grab the all-important goal, Rankin heading in from close range after a corner was headed on to him by Eddie Hutchinson.
Facing almost half a game with a lead against ten men, the Bees shut up shop and the home attack had little chance to earn the breakthrough they desperately needed.
With top scorer Adam Boyd bottled up, the home team always struggled up front and Brentford deserved their win.
They looked strong at the back and their mix of experience and hard running could pose problems for Premiership strugglers Southampton when they go to St Mary's next weekend.