The English forward has signed a Three-and-a- half year deal with the Toffees in a deal reportedly worth £20 million.
The Toffees reportedly beat out the likes of Southampton and Newcastle United for Walcott's signature.
“I’m very ambitious and I’ve come here because I want the Club to push to the next level,” Walcott told the club's official website.
“And with the players that have come in, I feel like the next level can be reached.
“I’m very excited to be starting a new chapter and I felt this was the right place for me to be.
“The manager is very ambitious and I feel like the Club is going in the right direction.