The 29-year-old, whose original contract was due to expire this summer, has committed himself to the Championship outfit until 2017.
"I'm delighted to see Christophe commit to a new contract here," manager Mick McCarthy told the club's official website.
"It's great news for Ipswich Town, as he's been absolutely fantastic for us since he first walked through the door. It's superb news."
Berra, who joined the Tractor Boys from Wolverhampton Wanderers last year, has scored three goals so far this season.