Aggius (Gallurese: Agghju, Sardinian: Azos) is a comune (municipality) in the Province of Olbia-Tempio in the Italian region Sardinia, located about 190 kilometres (120mi) north of Cagliari and about 35 kilometres (22mi) west of Olbia.
Aggius borders the following municipalities: Aglientu, Bortigiadas, Tempio Pausania, Trinità d'Agultu e Vignola, Viddalba.