Craig Mackail-Smith's fifth goal in three games helped take Brighton top of the Championship.
Gus Poyet's side handed Sheffield Wednesday a sound beating after taking a first-half lead through Wayne Bridge's deflected free-kick.
Mackail-Smith added a second in the 54th minute following a jinking run from Spanish full-back Bruno Saltor.
Will Buckley made it three from Bruno's lofted diagonal pass to seal Brighton's third straight win.
It means Dave Jones's Wednesday side have suffered back-to-back defeats after collecting seven points from their first three league games.
Buckley forced an early save from Owls' goalkeeper Chris Kirkland before Bridge's 24th-minute free kick looped in off Rhys McCabe.
The visitors struggled to create clear chances in the opening 45 minutes, and Jones brought on teenager Ross Barkley at half-time to make his debut.
Midfielder Barkley, signed on a month's loan from Everton, could not spark a revival though, and Brighton increased their lead nine minutes into the second half.
Bruno evaded a series of challenges as he cut into the penalty area from the right, and his low cross was stroked in by Mackail-Smith.
The full-back also created Brighton's third goal with a pass that caught out Wednesday's defence and found Buckley, whose first touch set up a cool, chipped finish.
Kirkland then kept out a Mackail-Smith header, with Brighton keeper Tomasz Kuszczak making excellent late saves to deny Jay Bothroyd and Joe Mattock.