The 29-year-old set up 20 goals in the 2019-20 campaign, equalling the record for most assists in a Premier League season set by Arsenal striker Thierry Henry in 2002-03.
He also scored a personal best 13 goals but was unable to help City defend their top-flight crown, with Pep Guardiola's side finishing 18 points behind champions Liverpool.
De Bruyne beat Liverpool trio Jordan Henderson, Sadio Mane and Trent Alexander-Arnold, Southampton striker Danny Ings, Leicester City's Golden Boot winner Jamie Vardy and Burnley goalkeeper Nick Pope to the award.
De Bruyne's former City team mate Vincent Kompany and ex-Chelsea winger Eden Hazard are the two other Belgians to win the accolade.
Alexander-Arnold was named Young Player of the Season earlier this week, while Juergen Klopp won the Manager of the Season award.
