The Eski Mosque (Greek: Εσκί Τζαμί, from Turkish: Eski Camii, "Old Mosque") is a mosque in the Greek town of Komotini dating back to 1608, or 1677/88, based on an inscription.

According to the 1892 Ottoman salname, the mosque featured an inscription in a "non-Ottoman" language, hence it is possible that the mosque was built on the site of a former Byzantine church.

In the 1910s, the Bulgarians turned the mosque into a church and destroyed part of the minaret (up to the Sherefe).

The building was returned to the Moslem minority in 1919-20, under the French administration of Komotini.

By then, the demolished minaret and the current 2 balconies were rebuilt.