Saints Theodore Tyro and Theodore Stratelates Church, or commonly known Saints Theodoroi () is a Greek Orthodox church and former cathedral in the city of Serres, in the Central Macedonia region of northern Greece. the old Byzantine cathedral of
Built as a cathedral in 1124, during the Byzantine era, the church is dedicated to Theodore of Amasea (Tyro) and Theodore Stratelates. Subject to destruction in 1205 during the Fourth Crusade, the cathedral-church was rebuilt in 1221; and again destroyed in 1913 during the Balkan Wars, and subsequently restored between 1938 and 1959.