The Argentine-bred Trezeguet had looked set to be on his way to Lyon or Valencia but changed his mind about leaving Juve.
"I am proud to link my name with Juventus for another four seasons," the 29-year-old Trezeguet said in a statement. "Today I have made a decisive choice for my career and my life. This is a club which has given me so much and with whom I want to continue to win."
Trezeguet stayed with Juve after it was stripped of its 2006 championship and demoted to Serie B for match-fixing. He helped Juventus return to Serie A, but he fell out of favor with French national team coach Raymond Domenech.
Juve is rebuilding for its return to Serie A under new coach Claudio Ranieri. Italy goalkeeper Gianluigi Buffon extended his contract, and Portugal's Tiago and Italian striker Vincenzo Iaquinta have joined the Turin club.