Telamon (Ancient Greek: Τελαμών, Telamōn, meaning "broad strap") in Greek mythology was the son of King Aeacus of Aegina and Endeïs, a mountain nymph. The elder brother of Peleus, Telamon sailed alongside Jason as one of his Argonauts and was present at the hunt for the Calydonian Boar. In the Iliad, he was the father of the Greek heroes Ajax the Great and Teucer by different mothers. Some accounts mention a third son of his, Trambelus. He and Peleus were also close friends of Heracles, assisting him on his expeditions against the Amazons and his assault on Troy.

In an earlier account recorded by Pherecydes of Athens, Telamon and Peleus were not brothers but friends. According to this account, Telamon was the son of Actaeus and Glauce, the latter being the daughter of Cychreus, king of Salamis; and Telamon married Periboea (Eriboea), daughter of King Alcathous of Megara.

After killing their half-brother Phocus, Telamon and Peleus fled Aegina and made their way to the island of Salamis, where King Cychreus welcomed Telamon and befriended him. Telamon married Cychreus' daughter Periboea, who gave birth to Ajax; sometime later, Cychreus gave Telamon his kingdom. In other versions of the myth Cychreus' daughter is named Glauce, and Periboea is Telamon's second wife and the daughter of Alcathous.

Telamon features in both versions of Heracles' sacking of Troy, which was ruled by King Laomedon (or Tros in the alternate versions). Before the Trojan War, Poseidon sent a sea monster to attack Troy.

Tros version: In the King Tros version, Heracles (along with Telamon and Oicles) agreed to kill the monster if Tros would give him the horses he had received from Zeus as compensation for Zeus' kidnapping of Tros' son Ganymede. Tros agreed; Heracles succeeded, and Telamon married Hesione, Tros' daughter, by whom he fathered Teucer.

Laomedon version: In the King Laomedon version, Laomedon planned to sacrifice his daughter Hesione to Poseidon in the hope of appeasing him. Heracles rescued her at the last minute and killed both the monster and Laomedon, along with Laomedon's sons, except for Ganymede, who was on Mount Olympus, and Podarces, who saved his own life by giving Heracles a golden veil Hesione had made. Telamon took Hesione as a war prize and married her, and she bore him Teucer. When Ajax later committed suicide at Troy, Telamon banished Teucer from Salamis for failing to bring his brother home.

Bibliotheca version: In Apollodorus' Library, Telamon was almost killed during the siege of Troy. He was the first to break through the Trojan wall, which enraged Heracles, who had coveted that glory for himself. Heracles was about to cut him down with his sword when Telamon began quickly to assemble an altar out of nearby stones in honor of Heracles. Heracles was so pleased that, after the sack of Troy, he gave Telamon Hesione as a wife. Hesione requested that she be allowed to bring her brother Podarces with her. Heracles would not allow it unless Hesione bought Podarces as a slave, so she paid for her brother with a veil. Podarces' name was then changed to Priam — which, according to Apollodorus, was derived from the Greek phrase "to buy."

In architecture, telamons are colossal male figures used as columns. These are also called atlantes (the plural of "Atlas") or atlantids; they are the male versions of caryatids.

The "Telamon" (also "Song of Telamon," "Telamon Song," or "Telamon-song") is an ancient Greek song (flourished 5th century BC) known only by name from references in some ancient Greek plays and later scholia or commentaries. It is usually thought to be a warlike song about Telamon's son Ajax, though some commentaries took it to be a mournful song about Telamon himself. It began: "Son of Telamon, warlike Ajax! They say you are the bravest..."