"I am thrilled to be signing for City and can't wait to get started," Walker said.
"Pep Guardiola is one of the most respected managers in the world and I feel he can help me take my game to a new level."
Txiki Begiristain, the Club's Director of Football, added: "Kyle is a fine full-back, one capable of producing quality at both ends of the pitch.
"We've followed his progress at Tottenham and have been really impressed by how he has developed. He is now one of the best right-backs in the Premier League and justifiably an England regular.
"I am sure he will be a success at Manchester City this season and beyond."