The central defender arrived at the club in 2012 and after a successful start to his career has committed his future to the club with a deal that runs until 2016.
Bassong made 35 appearances last season and after being named player of the year was made team captain by Chris Hughton at the start of the current campaign.
After a knee injury during pre-season he has gone on to make 10 appearances in the league this season and was happy to have extended his deal with the Premier League side.
"I'm really pleased, it is something I have been looking forward to doing," he told the club's official website.
"As being team captain I think it is something really important to commit myself even more to the club."
Hughton was pleased to have sorted out the future of the Cameroon international and reiterated his importance to the team.
"We're delighted that we've had the opportunity to extend Seb's contract," he said.
"(He is) somebody who has been an integral part of everything we've done so far and of course our player of the season last year."
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