Having struggled to establish himself in Italy last year, Eduardo feels a return to his homeland will benefit his career.
The 28-year-old has accepted an offer from the Portuguese giants after seeing Genoa turn their attention towards Inter Milan's Emiliano Viviano.
Benfica are happy to offer him first-team football, but accept that they must now move a goalkeeper on.
Spanish shot-stopper Roberto and Julio Cesar are expected to be offloaded before the transfer window slams shut.
That will allow Eduardo to battle it out with Artur Moraes and promising youngster Mika for the number one jersey.