Speaking at his first news conference, the Welsh midfielder said he was looking forward to embracing a new culture.
He joins the Italian giants from Arsenal, where his contract ran out in February after 11 seasons with the London side.
The 28-year-old is the third Welshman to play for the Turin side after John Charles, who played for them from 1957 to 1962, and Ian Rush.
Ramsey also said he hoped new Juve coach Mauricio Sarri would bring with him the success and style which marked his time at Chelsea.
(Production: Fabiano Franchitti)