If the answer above is None it means there is no specific mention in the legislation, but you still need to ask local law enforcement before drinking in Italy.
In 2012 the then Health Minister Renato Balduzzi proposed to raise the age to 18. Selling alcohol to those under the age of 18 in shops carries a fine between €250 and €1000. Serving alcohol beverages to those under the age of 16 is a criminal offense and is punished with prison up to one year, if the individual is 16 or 17 it will be treated as an offense that is fined between €250 and €1000 (Legge n. 189/2013).
You can find more legal details and links here:
Wikipedia Legal Drinking Page