The prolific Norwegian striker has put pen to paper on a deal that will keep him with the Premier League champions until 2034.
Haaland has scored 111 goals in just 125 games since joining City from Borussia Dortmund in 2022 and the length of his new contract is a Premier League record - beating the nine-year deal that Cole Palmer signed with Chelsea last year.
He said: "I am super happy. I am proud. It is difficult to put into words because it is a big moment. I am happy and that is the right word to use. I am looking forward to staying here for a long time. In the end, speaking with the people I spoke with, the hunger and the support that I have been getting for the last couple of years from the board, from the bosses and from Pep [Guardiola], it was an easy decision. I am delighted."
Haaland has won two Premier League titles since joining City - netting 52 goals as the club won a historic Treble in the 2022-23 season - and has vowed to improve even further after committing his future to the team.
The player - whose previous deal had been set to expire in 2027 - said: "I am going to stay for a long time. Now I can fully focus on getting better because I am going to stay here for such a long time. Full focus on performing and getting better to give all of the fans what they want.
"It has gone really quick. It feels like I signed a moment ago. It has been going really quick and that is a good thing. It means I am enjoying it.
"For two-and-a-half years as a City player I have been winning loads of trophies, playing loads of good football, having so many great moments together with the whole club and with the fans. I still remember the rainy parade [after the treble] which was maybe the biggest and best moment because it was a typical Manchester parade. It has been amazing and like a dream in this two-and-a-half years."