The 29-year-old has signed a three-year deal at the King Power Stadium and becomes Nigel Pearson’s first signing of the summer.
He said: “I’m happy that I’ve signed for Leicester City. It was always a goal for me to play in the Premier League, and I’m happy that this dream has come true.
“Everybody watches the Premier League. I think it’s the best league in the world. Leicester City is a new experience and new challenge for me.”
Fuchs has been capped 66 times by his country and made 99 league appearances for Schalke. He made 35 appearances last season, including in the Champions League, and scored three goals, one of which came in Schalke’s 4-3 win over Real Madrid in the Bernabeu.
Fuchs was also linked with a move to Swansea earlier this year but joins Leicester after their dramatic escape from relegation after a thrilling end-of-season rally.