Idaea or Idaia () referring to either the Cretan Mount Ida, or the Phrygian Mount Ida in the Troad, is the name of several figures in Greek mythology:

• Idaea, a nymph, who was the mother, by the river-god Scamander, of King Teucer.
• Idaea, the daughter of the Scythian king Dardanus, and wife of Phineus, who falsely accused her stepsons, leading to their imprisonment and torture.
• Idaea one of several epithets of Cybele, the great mother goddess of Anatolia, associated with Phrygian Mount Ida.
• Idaea, a nymph who was said to be the mother, by the shepherd Theodorus, of Erythraean Sibyl Herophile, and gave birth to her in a grotto at Erythrae.
• Idaea, the mother of the Kuretes () by an earlier Zeus who was, according to a tradition attributed by Diodorus Siculus to the Phrygians, the brother of Uranus and king of Crete, rather than the Olympian Zeus.
• Idaea, a nymph said to be the mother, by Zeus, of Cres who was said to be the eponym of Crete.
• Idaea or Ida, a daughter of Minos who was the mother of Asterion by Zeus. She might be the same with the above character.