The Gorgons (/ˈɡɔːrɡənz/ GOR-gənz; Ancient Greek: Γοργώνες), in Greek mythology, are three monstrous sisters, Stheno, Euryale, and Medusa, said to be the daughters of Phorcys and Ceto. They lived near their sisters, the Graeae, and were able to turn anyone who looked at them to stone. Euryale and Stheno were immortal, but Medusa was not and was slain by the hero Perseus.

Gorgons were dread monsters with terrifying eyes. A Gorgon head was displayed on Athena's aegis, giving it the power both to protect her from any weapon, and instill great fear in any enemy. Gorgon blood was said to have both the power to heal and harm.

Representations of full-bodied Gorgons and the Gorgon face, called a gorgoneion (pl. gorgoneia), were popular subjects in Ancient Greek, Etruscan and Roman iconography. While Archaic Gorgons and gorgoneia are universally depicted as hideously ugly, over time they came to be portrayed as beautiful young women.

The name 'Gorgon' is associated with the Ancient Greek adjective gorgós (γοργός), which, of an eye or look, means 'grim, fierce, awesome, dazzling', and is thought to derive from the Sanskrit stem garğ. The stem has connotations of noise, and Germanic and Romance languages have many derivatives from this stem referring to the throat (e.g. 'gorge') or the guttural sounds produced in the throat (e.g. 'gargle', 'gurgle'). It has been understood as meaning to growl, roar or howl, while Thalia Feldman suggests that the closest meaning for the stem might be the onomatopoeic grrr of a growling beast.

According to Hesiod and Apollodorus, the Gorgons were daughters of the primordial sea-god Phorcys and the sea-monster Ceto, and the sisters of three other daughters of Phorcys and Ceto, the Graeae. However, according to Hyginus, they were daughters of "the Gorgon", an offspring of Typhon and Echidna, and Ceto, while Euripides, in his tragedy Ion, has "the Gorgon" being the offspring of Gaia, spawned by Gaia to be an ally for her children the Giants in their war against the Olympian gods. Medusa had two offspring by Poseidon, the winged-horse Pegasus and the warrior Chrysaor.

Where the Gorgons were supposed to live varies in the ancient sources. According to Hesiod, the Gorgons lived far to the west beyond Oceanus (the Titan, and world-circling river) near its springs, at the edge of night where the Hesperides (and the Graeae?) live. The Cypria apparently had the Gorgons living in Oceanus on a rocky island named Sarpedon. Aeschylus's Prometheus Bound places them in the far east "across the surging sea" on the "Gorgonean plains of Cisthene", where the Graeae live, while his lost play Phorkides (another name for the Graeae) apparently placed them at "Lake Tritonis", a mythological lake set somewhere in westernmost North Africa. And the fifth-century BC poet Pindar has Perseus, apparently on his quest for the Gorgon head, visit the Hyperboreans (usually considered to dwell in the far north). However, whether Pindar means to imply that the Gorgons lived near the Hyperboreans is unclear.

Pherecydes notes that Medusa's face turned men to stone, and Pindar describes Medusa's severed head as "stony death". In Prometheus Bound, it says that no mortal can look at them and live. According to Apollodorus, all three of the Gorgons could turn to stone anyone who saw them.

Stheno and Euryale were immortal, whereas Medusa was mortal. According to Apollodorus' version of their story, Perseus was ordered by Polydectes (his enemy) to bring back the head of Medusa. So, guided by Hermes and Athena, he sought out the sisters of the Gorgons, the Graeae, who had only one eye and one tooth, which they shared. Perseus managed to steal their eye and tooth, and refused to return them, unless they would show him the way to the nymphs, which they did. Perseus got from the nymphs winged sandals, which allowed him to fly, and the cap of Hades, which made him invisible. He also received an adamantine sickle (harpē) from Hermes. Perseus then flew to Oceanus, where he found the Gorgons asleep. When Perseus managed to behead Medusa by looking at her reflection in his bronze shield, Pegasus and Chrysaor sprang from Medusa's neck, and Stheno and Euryale chased after him, but were unable to see him because he was wearing Hades' cap of invisibility. When Perseus brought back the Gorgon head, as ordered, he showed the head to Polydectes, who was turned to stone. Perseus returned the things he had acquired from the nymphs and Hermes, but gave the Gorgon head to Athena.