Part of the Demetrios Oikonomoloulos collection is displayed in the room 9. Demetrios Economopoulos died in 1986 leaving his collection to the Museum of Byzantine Culture in his will, which was executed in 1987 by his widow, Anastasia Zamidou-Ekonomopoulou.

The collection consists of 1460 artifacts dated between the prehistoric times and the 19th c., with the works of Byzantine and post-Byzantine art predominating in terms of both quantity and quality, a fact that reflects the collector's special interest in this period.

For the permanent display of the collection, which opened on May 27th 2001, representative works were selected from the categories of pottery, coinage, minor art, and ecclesiastical documents. Nevertheless the main part of the exhibit consists of icons dated between the late 14th and the 19th centuries. 146 items are on display. Their selection was made on the basis of their antiquity, artistic merit and the varied trends and schools of post-Byzantine art that they represent.