Hierotheos the Thesmothete (Greek: Ἱερόθεος ὁ Θεσμοθέτης) is the reputed first head and bishop of the Christian Athenians.

The title thesmothete means ruler, or junior archon, of Athens (literally "rule-setter").

Little is known of Hierotheos (Ἰερόθεος "sanctified by God"); church tradition holds that he was one of the learned men in the city of Athens.

He was instructed in Christianity by the Apostle Paul, who baptized and ordained him around the year 52 AD.

[3] Hierotheos stood in the midst of the apostles and comforted them with spiritual songs and hymns which he sang accompanied with musical instruments.