The Temple of Hephaestus or Hephaisteion, is a well-preserved Greek temple dedicated to Hephaestus; it remains standing largely intact today. It is a Doric peripteral temple, and is located at the north-west side of the Agora of Athens, on top of the Agoraios Kolonos hill. From the 7th century until 1834, it served as the Greek Orthodox church of Saint George Akamates. The building's condition has been maintained due to its history of varied use.

Hephaestus is the Greek god of artisans, blacksmiths, carpenters, craftsmen, fire, metallurgy, metalworking, sculpture and volcanoes. Hephaestus's Roman counterpart is Vulcan. In Greek mythology, Hephaestus was either the son of Zeus and Hera or he was Hera's parthenogenous child. He was cast off Mount Olympus by his mother Hera because of his lameness, the result of a congenital impairment; or in another account, by Zeus for protecting Hera from his advances.