The 29-year-old made the switch to Selhurst Park in 2011 from Turkish outfit Genclerbirligi, and will now remain with Tony Pulis' men until 2017.
Jedinak is a popular figure among Palace fans after skippering the side back to the Premier League for the first time since 2005 last season.
And the central midfielder is thrilled to extend his stay.
Speaking to the club's official website, he said: "I'm ecstatic to put pen to paper on a new ...
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