The Italian striker has confirmed on Twitter that a second year with the A-League club has been agreed to.
"I'VE CHOSE, SYDNEY Now it's official, I have renewed my contract with @SydneyFC," he wrote.
The second year of Del Piero's two-year deal, worth $2million, has been activated with the club today officially confirming the agreement.
"I am delighted to announce that Alessandro Del Piero will continue to be a Sydney FC player for the 2013/14 season," said Sydney FC Chairman Scott Barlow. "Alessandro's arrival at Sydney FC has been a wonderful success for Sydney FC and the A-League both domestically and internationally."
Del Piero added: "I am very happy to be staying at Sydney FC for another season.
"I have always said I want to continue that for next season but first we must work hard for success on the field for the rest of this season."