Three in ten Italians are on Facebook but just as many have never heard of it, think tank Eurispes said in its annual report Friday.
Almost 54% of the 25-34 age group and some 53% of the 18-24 age group use the social network, it said.
The majority of users are in central Italy while north-east Italy has the lowest percentage of users.
Almost half of people in Sardinia and Sicily are unaware that Facebook exists.