Church of Prophet Elijah, Byzantine church in Upper City, Thessaloniki, Greece

The Church of Prophet Elijah is a 14th-century Byzantine church in the Ano Poli of Thessaloniki, built in the cross-in-square "Athonite" type reserved for monastery katholika. Its walls alternate courses of brick and white ashlar, copied from Constantinopolitan practice. The photo shows a tall central drum with narrow arched windows and a cross, gabled roofs and smaller domed sections, and a lower row of arched porticos on rectangular pillars banded in brick and pale stone, with an arched doorway and small window behind them.

The church dates to the Palaiologan period, but its original dedication is unknown. It was long identified as the katholikon of the Nea Moni Monastery, founded c. 1360–c. 1370 on the site of a palace destroyed in 1342 during the Zealot uprising; modern research doubts this, since Nea Moni outlived the Ottoman conquest. Its interior decoration instead suggests the Akapniou Monastery. Badrah Mustafa Pasha turned it into a mosque after Thessaloniki fell in 1430.

The church's name comes from a misunderstanding: under Ottoman rule it was the Saraylı Mosque, "Palace Mosque", and this was later taken to mean the Prophet Elijah. Fragments of late-Palaiologan wall paintings survive inside; art historians link them to the Akapniou Monastery and trace their influence on later painting in Serbia.

The church sits in the Upper City of Thessaloniki and is reached on foot through narrow lanes in that part of town. The entrance faces east, and visitors should wear clothing that covers shoulders and knees before going inside.

The outer walls are built with alternating courses of white stone blocks and brick, a method rarely seen in Macedonia but widely used in Constantinople. This gives the building a visual rhythm on the outside that sets it apart from most churches in the region.