Didymóteicho (Greek: Διδυμότειχο, [ðiðiˈmotixo]) is a town located on the eastern edge of the Evros regional unit of East Macedonia and Thrace, in northeastern Greece. It is the seat of the municipality of the same name. The town (pop. 9,263 in 2011) sits on a plain and located south east of Svilengrad, south of Edirne, Turkey and Orestiada, west of Uzunköprü, Turkey, about 20 km north of Soufli and about 90 km north of Alexandroupoli. The municipality of Didymóteicho has a land area of 565.4 km² and a population of 19,493 inhabitants.

Didymoteicho is just 2 kilometers away from the Greek-Turkish border, and as a result it is home to many Greek military units and Hellenic Army training centers. Hundreds of thousands of Greek men had to either receive military training or spend part of their military service here (see conscription in Greece). The famous 1991 George Dalaras and Lavrentis Machairitsas song Didymoteicho Blues (Greek: Διδυμότειχο Μπλουζ) pays homage to the personal stories and experiences of these soldiers while offering a more general commentary about life in the Army.