The result means City, who had to come from behind to beat the Seagulls, finish one point above Liverpool in the final table but they have had to win 14 league games in a row since losing at Newcastle United in January to see off Jurgen Klopp’s side.
City had an early penalty appeal waved away by referee Michael Oliver when Bernardo Silva went down under Mat Ryan’s challenge.
The Seagulls were lively in the opening stages though and Alireza Jahanbakhsh curled a 25-yard left-footed shot narrowly wide of Ederson’s goal.
Sergio Aguero had a shot blocked by Shane Duffy before Ryan kept out Riyad Mahrez’s deflected effort.
It seemed only a matter of time before City took the lead but Chris Hughton’s team scored the opening goal against the run of play in the 27th minute when veteran striker Glenn Murray glanced a header from a corner past Ederson.
City’s response was immediate though with Sergio Aguero equalising 83 seconds later with a smart finish after being set up by David Silva.
Pep Guardiola’s team poured forward and, after Mahrez had been denied by Ryan, the visitors took the lead in the 38th minute when an unmarked Aymeric Laporte headed home from a corner.
On the stroke of half time Brighton almost equalised though with Ederson having to make a good save to keep out Lewis Dunk’s dipping free-kick.
City remained on top at the start of the second period and Mahrez twice went close to extending their advantage before Ilkay Gundogan saw his goalbound shot blocked.
Former Leicester City star Mahrez grabbed the third goal in the 63rd minute - his excellent strike beating Ryan and finding the top corner of the net - and Gundogan put the seal on the victory nine minutes later with a sublime free-kick.
Guardiola’s team strolled through the rest of the match, conserving their energy before next weekend’s FA Cup final against Watford as they aim to complete an unprecedented domestic treble.