City confirmed the news on Twitter as well as on their official website.
The Tweet read:
The official statement from Manchester City read: "Manchester City are delighted to announce the signing of Leroy Sane from Schalke 04.
"The German international becomes our fifth signing of summer 2016 and will wear the No.19 shirt. Sane has signed a five-year deal which will keep him at the Etihad Stadium until at least 2021."
After signing for English side, Sane spoke to the club's official site where he said: "I feel really good, I'm happy to be here and happy that it has all worked out. Now I can settle here in Manchester and play for City.
"One of the reasons I decided to join City was Pep Guardiola; he convinced me to come here and that I can continue to progress. I know I will learn a lot under him and now I can take the next step in my career.
"I followed Pep at Barcelona and at Bayern where he achieved a lot and worked really well with young players.
"I think he can make me a more complete player. I think I will need a bit of time to start with because it's another league and there's a different style of play but I think I can adapt very quickly."
After completing his fifth signing, manager Pep Guardiola said:"He is a special talent, and an exciting player that I think our supporters will enjoy watching.
"He has great technical ability, is comfortable on the ball and there is much to admire about the way he plays football. He is fast, enjoys creating chances for others, works hard for the team and scores goals, too. He also has a very positive attitude and will fit in well with our squad.
"At 20, he is still developing as a player but he is already a member of the German national side and I think he will be a fantastic asset to our Club. We are very happy he decided to join us."