The Ibrahim mosque is situated in the southwest corner of the Qasr Ibrahim, bordering the fortified city of al-Hufuf. According to an inscription above the main entrance, the mosque was erected in 1569-1570. Built of mud brick and stone covered with a local plaster, the mosque sits on an elevated brick platform within the courtyard of the Qasr. The south and west walls of the mosque are adjacent to the castle walls, while the north and east mosque walls remain open to the Qasr courtyard. These north and east walls are faced by a portico of pointed arches supported on large circular columns and roofed by a series of circular domes; some of these arches are decorated with circular lobes. The mosque has two outdoor mihrabs: one, within an undecorated pointed arch, is on the qibla side of the northern portico, and the second, which is freestanding, is located to the east of the mosque.
The mosque is entered through two doors situated in the east and north walls. The main entrance on the eastern wall faces the qibla wall in the axis of the mihrab, and is differentiated from the northern entrance by incised plaster decoration depicting scrolls and geometric patterns on the arch intrados. The prayer hall is composed of a single square space roofed with a dome supported on squinches. Each squinch is topped by a small circular dome visible from the exterior. The qibla wall to the west is preceded by an elevated platform and holds an arched mihrab topped by a muqarnas semi-dome. To the right of the mihrab, three built-in steps adjacent to the wall define the minbar.
The prayer hall is lit by six ground floor rectangular windows flanking the two entrance doors and the mihrab on the qibla wall. Three more windows along the southern wall are rendered useless due to the proximity of the castle's walls. Additional arched windows are located above the mihrab, above the entrance, and below the dome. These are covered with carved plaster mashrabiyyah screens.
The mosque has a single minaret located at the northeast corner of the mosque forming a salient curve in the portico, where it is entered. Differing from the usual Ottoman style, it more closely resembles Iraqi and East Arabian minarets, with a circular shaft that tapers slightly ringed by a muqarnas-supported circular balcony. This balcony has a wooden balustrade and elaborate wooden arches that support the roof. The minaret ends in a slightly pointed dome decorated with a metallic crescent.