Old Mosque, Ottoman mosque in Komotini, Greece.

The Eski Mosque is a mosque in central Komotini featuring a square prayer hall, a single minaret, and traditional brick construction. The building displays Ottoman architectural elements throughout its interior and exterior design.

According to Evliya Çelebi the mosque dates from 1608/9, or 1677/78 by an inscription. It likely began as the first mosque of Komotini, founded as a mescit by Gazi Ahmed Evrenos within his vakıf complex with the adjoining imaret and hamam. Renovated in 1854, it was turned into a church by Bulgarians in the 1910s, who destroyed part of the minaret; it was returned to the Muslim minority in 1919–20 under French administration, when the minaret and two balconies were rebuilt.

The mosque reflects the long presence of Muslim life in the city through its architecture and daily use. Today it serves as an important gathering place and prayer space for the local community.

The building is regularly used for prayers by the Muslim community of Komotini and is generally accessible to visitors. Following major renovations, the interior is well maintained and straightforward to view.

The 1892 Ottoman salname records an inscription in a "non-Ottoman" language inside the mosque, which is why a Byzantine church is thought to have stood on the site before Evrenos founded the first mescit here. The building is also called the Mosque of Two Balconies, both added after 1919.