In Greek mythology, Tenes or Tennes (Ancient Greek: ) was the eponymous hero of the island of Tenedos. He was the son either of Apollo or of King Cycnus of Colonae by Proclia, daughter or granddaughter of Laomedon. Cycnus's second wife Philonome, daughter of Tragasus or Cragasus, falsely accused Tenes of rape, bringing in a flutist named Eumolpus as witness. Cycnus believed the accusations and tried to kill Tenes and his sister Hemithea by placing them both in a chest, which was set into the ocean. However, the chest landed at the island of Leucophrye, which was later renamed Tenedos, and the two survived. The natives of the island pronounced Tenes their king. Cycnus later learned the truth, killed Eumolpus, buried Philonome alive and tried to reconcile with his children, but Tenes rejected his overture: when Cycnus's ship landed at Tenedos, Tenes took an axe and cut the moorings.
Tenes fought with Achilles when Achilles had tried to assault his sister. Though his sister escaped, Tenes died when Achilles plunged a sword into his heart. Even though Thetis had previously warned her son against doing so, for Tenes's death would be avenged by Apollo, Achilles was heedless and sealed his death by Apollo's hands. Shortly after the end of the Trojan War, Agamemnon permitted the Trojan prisoners of war to build a city north of Mycenea. The city was called Tenea after Tenes. A description on the history of Tenea was also given by Pausanias.
Diodorus Siculus relates that the Tenedians founded a sanctuary of Tenes to commemorate his virtues. No flute player was allowed to enter the sacred precinct, and the name of Achilles was not to be uttered in it. Sacrifices were offered to Tenes until recent times.