Brentford started the match on fire, with Yoane Wissa's shot saved by Brighton's goalkeeper Bart Verbruggen. But the home side didn't let up, and on the ninth minute, Keane Lewis-Potter's pass found Bryan Mbeumo, who confidently slotted past Verbruggen.
Brighton finally got a chance on goal in the 30th minute, but João Pedro's effort went wide. Just before halftime, Brighton equalized through Danny Welbeck's header from Mats Wieffer's cross.
Brentford came out strong in the second half, and Mbeumo's left-footed strike deflected off Lewis Dunk's chest and into the net. The Bees doubled their lead when Wissa's strike deflected in via Jan Paul van Hecke.
Brighton's day went from bad to worse when João Pedro was sent off for a red card after clashing with Nathan Collins. Despite being down to 10 men, Brighton pulled a goal back through Kaoru Mitoma, but Brentford held on to secure the win.
Mbeumo's double performance earned him the Flashscore Man of the Match award. Brentford's victory moves them within two points of Brighton in the race for European places and ends a five-game losing streak against the Seagulls.
Catch up on the match here.