The midfielder has won 16 trophies at City since joining the club from Wolfsburg in 2015 but his time at the Etihad Stadium will come to an end when his contract expires this summer.
De Bruyne - who has won six Premier League titles and the Champions League with City - wrote on social media: "Every story comes to an end, but this has definitely been the best chapter.
"Football led me to all of you - and to this city. Chasing my dream, not knowing this period would change my life. This city. This club.
"These people gave me everything. I had no choice but to give everything back. And guess what - we won everything.
"Whether we like it or not, it's time to say goodbye. Suri, Rome, Mason, Michele, and I are beyond grateful for what this place has meant for our family. Manchester will forever be on our kids' passports - and more importantly, in each of our hearts.
"This will always be our home. We cannot thank the city, club, staff, team-mates, friends, and family enough for this 10-year ride."
De Bruyne has scored 106 goals in 413 games for City and the club are planning a "fitting tribute" to the Belgian playmaker before the end of the season.
The Premier League champions said: "Manchester City will bid an emotional farewell to Kevin de Bruyne this summer when his contract expires, bringing an end to a glittering 10-year period at the club.
"The Belgian, a global icon of the game, has played 413 matches for City.
"During that period, he has scored 106 times, making him the first City midfielder since Colin Bell to reach a century of goals.
"The club and all of our fans will now take the time to deliver a fitting tribute and farewell to one of the greatest players to ever play in the Premier League."