The Brazil international has been a regular in PSG's first team since joining from Barcelona in January 2012, making 128 appearances in all competitions.
During his time at the Parc des Princes Maxwell has won the league title on two occasions and the Coupe de la Ligue last term.
"I am very proud of the confidence placed in me by the president Nasser Al-Khelaifi and the whole club," he told PSG's official website.
"I will continue to give everything to help the club try and reach its objectives."
As well as his success in the French capital, Maxwell has also won the domestic leagues in Netherlands, Italy and Spain with Ajax, Inter and Barcelona, while he also lifted the UEFA Champions League with the Catalan giants.
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