Tadasuni is a comune (municipality) in the Province of Oristano in the Italian region Sardinia, located about 100 kilometres (62 mi) north of Cagliari and about 35 kilometres (22 mi) northeast of Oristano. As of 31 December 2004, it had a population of 187 and an area of 4.6 square kilometres (1.8 sq mi).[3]