Di Stefano was in a coma for a month following a November 30 attack by four unidentified thieves at his villa in Diani, southeast of Nairobi, Kenya.
The singer suffered severe head injuries trying to protect his wife from the attackers. He underwent two operations in a hospital in Mombasa before being transferred to San Raffaele hospital in Milan.
He awoke from his coma at the end of December.
The Sicilian-born di Stefano was considered one of the greatest voices of the 1960s and 70s.