The former West Ham star has signed a three-year deal with the Premier League champions.
Chelsea will cost the 30-year-old around £5million.
“We are happy to have this new player,” manager Carlo Ancelotti told Chelsea’s official website.
“Yossi has a lot of quality in midfield and can play in lots of positions. I like his behaviour on the pitch and he will do a great job for us next season.”
“I am very excited to come to a club like Chelsea, it is a big club and I think it is a dream for every player,” Benayoun said.
“Hopefully we will be successful.”
