Town maintained the impressive home form this season with a fourth win from five thanks to a brace from the in-form David McGoldrick.
The striker sent Blues on the way with a 25 yarder that took a deflection just past the quarter hour and then showed slick footwork – and a couple of stepovers - before burying his shot in the bottom corner to take his goal tally to five for campaign.
McGoldrick had chances for a third, firing over early in the second-half and then seeing another goalbound effort deflected wide but his first-half double had done the damage ending Brighton’s six match unbeaten run.
Town boss Mick McCarthy stayed with the same side that had played so well at Wigan last weekend without getting any reward, Jack Marriott the only change to the 18 – the teenager replacing Paul Taylor - who begins his month loan at Peterborough - on the bench.
Brighton started well and should have been ahead on six minutes, Will Buckley escaped down the right flank and from his cross, Andrew Crofts blazed wide from eight yards.
It was Blues who made the breakthrough though on 18 minutes, McGoldrick showing quick feet to create an opening 25 yards out, his shot taking a deflection to wrong foot Tomasz Kuszczak.
There was nothing fortunate about the second goal five minutes later, McGoldrick twisting and turning Gordon Greer inside out before curling the ball into the corner.
The summer arrival from Nottingham Forest was close to capitalising on a mistake by former Town loanee Keith Andrews soon after but the ball span away from danger.
Buckley almost got in at the other end as Brighton looked to respond, Cole Skuse then coming to Town’s rescue with a superb tackle as Crofts threatened on the edge of the box.
Ashley Barnes had the final shot of the half, firing over as Town held firm to take a two goal advantage into the break, the Seagulls restricted to Crofts’ early chance.
McGoldrick had a gilt-edged chance to wrap up the points two minutes into the second-half. A surging run by Ryan Tunnicliffe opened up the Brighton defence, Daryl Murphy found his strike partner with a short pass but McGoldrick couldn’t keep his shot down.
Slick passing between Tunnicliffe and Aaron Cresswell saw the full-back in on goal before a timely intervention from Greer as Town pressed for a third.
Murphy headed over from Cresswell’s cross, while at the other end Christophe Berra was in the right place to first deny Barnes and then Inigo Calderon.
Kazenga Lualua, on for Craig Conway, fired wide – his pace giving Brighton an attacking edge down the left.
Town changed it around midway through the half with Carlos Edwards and Frank Nouble replacing Paul Anderson and Murphy.
Nouble was inches away from converting Cresswell’s free-kick at the far post, while Calderon fired over from the edge of the box as Brighton looked for a way back into the game.
McGoldrick and Cresswell sent free-kicks over the bar, Edwards then linking up with Nouble but his dipping volley went over.
McGoldrick left the field to a standing ovation five minutes from time, his goals lifting Town above Brighton and into the top 10.