Damastes of Sigeum was a 5th-century BCE Greek historian and geographer, a contemporary of Herodotus. Ancient sources indicate he was a student of the historian Hellanicus of Lesbos. He came from Sigeum in the Troad, placing him within the Ionian intellectual tradition.

His fragmentary works include Events Concerning Greece and Persia, a historical account; On Poets and Sophists, a biographical catalog; and Circuit of the Earth (or Periegesis), a geographical treatise.

Damastes is a minor logographer of the pre-Thucydidean tradition. His fragments show he contributed to early historiography and geography, blending myth, genealogy, and history. Later authors like Strabo and Harpocration cite him for details on genealogies and place names.