The 23-year-old had been linked with a move away from the Philips Stadion during the close-season after impressing at the World Cup in Brazil, with Napoli reported to be among those showing an interest.
However, Wijnaldum has put an end to any speculation by signing a fresh deal, with PSV announcing the news on their official Twitter account.
""Georginio Wijnaldum has put his signature onto a new contract that keeps him at PSV until 2018," the club tweeted.
"Congratulations Georginio!"
After moving from Dutch rivals Feyenoord in 2011, the attacking midfielder has gone on to make 111 appearances for PSV, scoring 38 goals.
He started for PSV in their opening match of the new season on Sunday as they beat Willem II 3-1 and spoke of his desire to sign a new deal after the victory.
Wijnaldum featured in all seven of the Netherlands' games at the World Cup, starting the last five and scoring in the third-place play-off with hosts Brazil.
