The 20-year-old has long been embroiled in discussions over a new deal, but talks had stalled earlier on this week as Napoli prepared to make the midfielder a "monstrous" offer.
However, speculation over the Italy international's future has now finally been put to bed after his agent revealed the player is set to sign a new deal until 2018.
"The deal is reached with PSG," wrote Donato Di Campli on Twitter.
"Marco Verratti will remain until 2018. The contract signing will occur after his return from the game in Gabon."
Verratti joined the Ligue 1 champions in the summer of 2012 from Pescara and made a total of 39 appearances for the club last season.