In Greek mythology, Idmon (Ancient Greek: Ἴδμων means "having knowledge of" or "the knowing") may refer to the following individuals:
- Idmon, one of the fifty sons of Aegyptus, who married and was killed by the Danaid Pylarge.
- Idmon, father of Arachne, and perhaps her brother Phalanx too.
- Idmon, an Argonaut seer and son of Apollo or Abas, and Princess Cyrene.
- Idmon, herald of Turnus.
- Idmon, a figure briefly mentioned in Statius' Thebaid. He came from Epidaurus and was portrayed in the poem cleansing Tydeus' wounds after a battle.