[1] The mosque received its name from Ibrahim Efendi, an Ottoman minister of finance (defterdar), who ordered its construction at the close of the 18th century.

[3][4] Standing on Eleftherias Square in the town of Kos, it is a two-story building of cubic form, with an octagonal dome supported by twelve arches.

[2] On the first floor there is the square prayer room, which through two doors communicates with the narrow and elongated narthex to the north.

The eastern staircase, the top of which is covered by a double-domed propylon, was intended for the entrance of officials to the mosque.

[2] On the west side of the mosque stands the minaret, which has a single portico with a parapet, while a little beyond there is a marble octagonal fountain, covered with a vaulted building supported by six arches and short columns.