In Greek mythology, Phthia (/ˈθaɪə/; Greek: Ancient Greek: Φθία or Φθίη, romanized: Phthía) may refer to the following individuals:
Phthia, the nymph mother of Dorus by Hellen, the progenitor of the Hellenes, according to Vitruvius's De architectura.
Phthia, the beloved of Apollo, by whom she became the mother of Dorus, Laodocus, and Polypoetes.
Phthia, daughter of Phoroneus and mother of Achaeus by the god Zeus. This version is to some extent confirmed by Aelian, who relates that Zeus assumed the shape of a dove to seduce a certain Phthia.
Phthia, a Theban princess who was one of the Niobids, children of Amphion, king of Thebes, and Niobe, daughter of Tantalus.
Phthia or Clytia, the concubine of Amyntor who falsely accused her stepson, Phoenix, of seduction causing his father to blind him.