The France international has been a regular fixture in the Gunners’ rearguard this season and has made 31 Premier League appearances.
“I am very proud to have reached agreement with the club on a new contract,” said Koscielny.
Laurent has proven himself to be an outstanding player since joining us
“I have enjoyed four great years at Arsenal already, and I look forward to continuing to help the team in the years to come.”
The length of the 28-year-old new deal has not been disclosed by Arsenal, although it is believed to be five years.
Arsenal boss Arsene Wenger added: “Laurent has proven himself to be an outstanding player since joining us in 2010 and has showed his quality once again this season.
“I am delighted he has decided to commit his future to the club.”
Koscielny has made 163 appearances for the Gunners in all competitions, more than any other Arsenal player over the same period.
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