Saint Mary Koumbelidiki, Eastern Orthodox church in Kastoria, Greece.

Saint Mary Koumbelidiki is a small rectangular church in Kastoria's acropolis, near the fortress wall. Its square core is covered by a circular dome on four arches, set over three semicircular conches, with a narrow inner narthex and a later outer narthex to the west. The tall cylindrical drum carries ceramic ornament and glazed tiles.

Most scholars, including Gabriel Millet and Anastasios Orlandos, date the church to the 10th–11th century, though some propose the 9th century. It was first named Skoutariotissa, as recorded in an inscription at the base of the dome; the name Koumbelidiki, from the Turkish word for dome, dates from Ottoman times. The dome was largely destroyed in the Italian bombardment of 1940 and rebuilt in 1949.

The name Koumbelidiki comes from the Turkish word kubbe, meaning dome, given in Ottoman times; an inscription at the dome's base records the older name Skoutariotissa. The west facade carries the Dance of Salome of 1496, a rare subject, and the inner narthex arch shows the Trinity with the Holy Spirit as a dove.

The church stands in the acropolis of Kastoria, close to the fortress wall, and its entrance is on the west side. The floor is paved with ceramic tiles, and a protective canopy was extended over the exterior west wall to shield the frescoes from rain and sun. Visits are best timed for daylight, when the painted surfaces are legible.

The rare Trinity in the inner narthex vault shows Christ Pantocrator holding a glory with the Holy Spirit as a dove. The 1496 frescoes on the west facade, funded by Andronikos, include the Dance of Salome, a scene seldom painted in Byzantine churches.