Eleutherius, Eleutherus or Eleuterus may refer to:

Gods

• An epithet of Dionysus and Zeus, meaning 'The Liberator'

Saints

• 2nd century Pope Eleutherius (feast day: May 26)
• Eleutherius of Rocca d'Arce (feast day: May 29), English pilgrim who died at Rocca d'Arce
• Eleutherius of Nicomedia (feast day: October 2), a soldier who was martyred under Diocletian
• Eleutherius of Tournai (died 532), bishop of Tournai, 5th century evangelist of the Franks
• Eleutherius and Antia (feast day: died 121), martyrs
• the martyred companion of Saint Denis of Paris (martyred c.250, feast day: October 9)

Bishops

• Eleutherius, Bishop of the west Saxons

Patriarchs and exarchs

• Eleutherius of Byzantium, Patriarch of Constantinople (129–136)
• Eleutherius, Greek Patriarch of Antioch (1023–1028)
• Eleutherius, Greek Patriarch of Alexandria (1175–1180)
• Eleutherius (exarch) (died 620), 7th century Exarch of Ravenna