Savona moves to the City Ground on a five-year contract and joins for a fee rising to €15.5m.
He said: “I am very excited to be here. It is a new experience for me as a person and a player. It is such a historic club, and the move is a dream come true.
“I can’t wait to play in front of the fans at the City Ground, and I will give my all for the shirt.”
Chief Football Officer, Ross Wilson, said: “Nicolò gained great experience with Juventus last season, and we’re really pleased he is joining us for his next step.”
“He is a versatile player who will be another strong option in our defensive unit, and we are convinced he will continue to develop here at Forest. He understands the demands of playing for a big Club and arrives here keen to make an impact straight away. We look forward to welcoming him to our group.”