The Brazil centre-back joined PSG from Serie A side Roma in July 2013 after just a year in the Italian capital.
Marquinhos has made 31 appearances for Laurent Blanc's men this term and been widely linked with a move away from the Parc des Princes.
Premier League outfits Manchester United and Chelsea had been credited with an interest in the former Corinthians man.
But upon signing his new contract Marquinhos told the PSG's official website: "This is a great success, good news. This means that the job is done.
"This is a new stage in my life. The project here is beautiful... and life is beautiful in Paris.
"I am very happy, pleased with everything that happens in my life.
"Paris Saint-Germain brought me a lot of good things. I hope this will continue."
PSG sit top of Ligue 1, a point clear of nearest rivals Lyon, and will face Barcelona in the quarter-finals of the UEFA Champions League.
Club president Nasser Al-Khelaifi added: "Marquinhos is the future of the club and the renewal of his contract is a strong signal of his commitment to Paris Saint-Germain.
"We are very pleased to continue our adventure with this very talented young player.
"While the biggest clubs in Europe followed Marquinhos, this extension strengthens and reinforces the ambition of the new long-term project of Paris Saint-Germain."
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