The 29-year-old played another pivotal role to help Pep Guardiola’s men win the Premier League title for the third time in four seasons.
De Bruyne featured 25 times in the top flight, scoring six goals and laying on 12 assists for his teammates.
De Bruyne came out on top in a six-man shortlist that included teammates Ruben Dias, Ilkay Gundogan and Phil Foden as well as Harry Kane and Bruno Fernandes.
The Belgium international is the third player to win the PFA gong in successive seasons after Thierry Henry and Cristiano Ronaldo.
"The fact the players chose me for this award means that I've done very well," said De Bruyne.
"You want to win all the trophies with the team and this is probably the most important one as an individual trophy in the league. To be voted by your competitors, by players who you compete with every game - to choose you, that says a lot.
"They're the people in my view who know the most about the game.
"When you have these things you can show your kids and say 'Look! this is what Daddy did when he was younger'."
De Bruyne has been cleared to feature in EURO 2020 after getting injured in the Champions League final on May 29.
