Perdaxius (, ; also spelled in Sardinian) in sardinian language, is a (municipality) in the Province of Sulcis Iglesiente in the Italian region Sardinia, located about west of Cagliari and about east of Carbonia. On 31 December 2004, it had a population of 1,466 and an area of .
Perdaxius borders the following municipalities: Carbonia, Narcao, Tratalias, Villaperuccio.