The National Union of Greece (Greek: Εθνική Ένωσις Ελλάδος, Ethniki Enosis Ellados or EEE) was a far-right political party established in Thessaloniki, Greece, in 1927.

Registered as a mutual aid society, the EEE was founded by Asia Minor refugee businesspeople.

Its members were in political and, especially, commercial antagonism with Thessaloniki's substantial Jewish population.

Owing to its military uniforms and organisation, the party was commonly referred to as "The Three Epsilons" (τα Τρία Εψιλον) or "The Steelhelmets" (οι Χαλυβδόκρανοι), in allusion to the German paramilitary Der Stahlhelm.

It gained a revival in 1941 when Nazi Germany captured Thessaloniki and put it in charge and then it also changed its name to "Εθνική Σοσιαλιστική Ένωση Ελλάδος" (National Socialist Union of Greece) and it also ran the collaborationist newspaper.