This structure has been dated by archaeologists to the late eleventh or early twelfth century, although there is evidence that it is built on the site of an earlier church, which was itself erected on the ruins of an ancient building. The present church was originally dedicated to St. Theodore and served as the chapel for an adjacent monastery of that name. The monastery was destroyed at some time early in the Turkish period, after which the church was abandoned for a time and fell partly into ruins. Then in 1769 the church was acquired by the Monastery of St Catherine on Mount Sinai, at which time it was restored and dedicated to Hagia Aikaterini. 
The church was rebuilt and enlarged in 1927, so that only the dome and the central apse remain from the original structure. The church is cruciform in plan, with the dome resting on a very high octagonal drum which is supported internally by four columns, with the usual narthex to the west and to the east a large central apse flanked by smaller apses on either side. Hagia Aikaterini is one of the most popular churches in Athens, and its spacious courtyard and pretty garden make it a favorite for weddings and baptisms.