The Hatters had got through to half time unscathed, before falling 2-0 behind as Neal Maupay and Ben Mee scored.
Sub Jacob Brown pulled one back on 76 minutes only for Shandon Baptiste to seal victory and to find out how the Town players rated on the afternoon, see below.
5. Teden Mengi: 6
Like the rest of Town's defence, he was looking solid in the opening 45 minutes as the Hatters' gameplan, in terms of keeping the Bees out, appeared to be working. Another who couldn't quite react to the half-time change at the back either as Luton's plans went up in smoke. Made a wonderful sliding block to prevent Wissa from scoring midway through the second period, but injured his knee in the process and had to go off, but hopefully it won't see him adding to Luton's defensive injury crisis. Photo: ADRIAN DENNIS
6. Amari’i Bell: 6
After a tough opening few minutes against Mbeumo when Brentford's main threat looked to get at him whenever possible, the wingback reacted well to the challenge, able to get a grips with the winger as his threat was kept to a minimum. Dropped back into the back three for the second period due to injuries as on the whole, Town's defence just didn't cover themselves in glory, with the hosts gifted three easy goals. Photo: ADRIAN DENNIS
7. Pelly-Ruddock Mpanzu: 5
Had one moment in the first half where he shrugged off two markers and looked to break forward, but unfortunately the move, as his impact on the game did, rather tamely fizzled out. Tried to spread the play a few times, but unfortunately his passes went astray as Brentford were able to completely dominate the midfield areas. Replaced on the hour mark in a triple change by Edwards. Photo: Marc Atkins
8. Ross Barkley: 6.5
Was the one shining light in the middle for Luton as the few times he was able to get on the ball, he could relieve some pressure on the visitors' back three. Limited in the first half as the Bees had control, but once Town started to give it a go at 2-0 down, was able to find some space and thread a pass through for Brown to get away and pull one back. Saw plenty of the ball in the closing stages, having a number of shots charged down by the Brentford defenders. Photo: ADRIAN DENNIS