The Italy international, whose previous contract was due to expire this summer, will now stay in Turin until June 30, 2016.
Pirlo, 35, helped the Bianconeri to clinch their third straight Scudetto by scoring four goals in 29 league appearances this term. He was named the Serie A Player of the Year twice during his tenure at Juventus and was voted as the Italian Player of the Year in 2012.
The veteran midfielder joined the club three years ago from AC Milan and since then, has been a regular in Antonio Conte’s first team.
Pirlo is currently in Brazil with Italy World Cup squad preparing for their Group D match against England on Saturday.