The attack happened after he tried to intervene in a road rage incident.
He had been travelling with his family in the Apulia region when he attempted to claim the drivers' tempers, La Gazzetta del Mezzogiorno reported.
Despite identifying himself as a policeman, he was set upon by two men and beaten. A fellow officer in the area attempted to stop the attack but he too was assaulted.
An emergency services helicopter was sent from Bari and the attackers were arrested, the newspaper said.
Leonardo D’Ercole, 41, and 26-year-old Leonardo Ricucci are accused of grievous bodily harm and violent against a public official.
In addition to ripping off the first policeman’s ear the men reportedly caused multiple facial fractures, while his colleague suffered concussion and other minor injuries.