The mosque bearing the name of Mezit Bey was built in Edirne in the years 1440-1441. Initially, the building served as the quarters of the religious fraternity of the dervishes and a medrese. It was later transformed into a mosque. The complex of buildings surrounding the mosque also included a soup kitchen (so-called imaret), a bathhouse, and a hotel for travellers (tabhane). All these structures were destroyed by an earthquake in 1752.

Mezit Bey, the founder of the mosque, was an Ottoman military commander serving during the reign of Sultan Murad II. In 1442, he invaded Transylvania with a force of 17,000 soldiers, taking John Hunyadi by surprise and winning the first battle near Marosszentimre (now Sântimbru in Romania). Next, Mezit Bey lay siege to Hermannstadt, but the forces of Hunyadi forced the Ottomans to lift the siege. Mezit Bey died in the battle at Gyulafehérvár where the Ottoman forces were annihilated.

The second name of the mosque, more commonly used is Yeşilce Camii i.e. the Greenish Mosque. It refers to the green colour of the tiles, which once lined the interior of the building. Unfortunately, they have not been preserved to our times, and now the interior walls of the mosque are simply painted white. Round shields painted with the Arabic calligraphy, placed in the main prayer hall, are the main elements of the interior decoration.

The mosque was built on an inverted T plan, without a front portico. A single minaret with one balcony rises in the northwest corner of the mosque. The walls of the building were erected of stone blocks and bricks.

The interior of the mosque is divided into four parts, each built on a square plan. The largest hall, which houses a stone mihrab and a wooden mimbar, is covered with an octagonal vault that supports the hemispherical dome. The other three rooms are covered with smaller domes based on octagonal drums.

The interior of the mosque is illuminated by two rows of windows. The upper windows also play an ornamental function, as they are filled with geometric, multicoloured stained glass. Near the entrance to the mosque, there is a wooden balcony, which serves as a place for women. Over this balcony, a huge calligraphy is painted on the wall.

After the earthquake of 1752, which destroyed the remaining buildings belonging to the complex, only the mosque was rebuilt. Another renovation of the building took place in 1889 when the mihrab was added.