Eduardo says he welcomes a 'new challenge' after joining Chelsea from Dinamo Zagreb.
The 33-year-old goalkeeper has signed a one-year deal at Stamford Bridge and will provide back-up for Thibaut Courtois and Asmir Begovic.
He played his final match for the Croatian champions on Wednesday night as they beat Salzburg to secure their place in the Champions League group stage.
Eduardo, who was part of Portugal's Euro 2016-winning side, said: 'Having the opportunity to come to the Premier League and to Chelsea, to such a big club, it is an easy decision to make.