The ground plan of the Umayyad Mosque is rectangle in shape and measures 97 meters (318 ft) by 156 meters (512 ft). A large courtyard occupies the northern part of the mosque complex, while the haram ("Sanctuary") covers the southern part. The courtyard is enclosed by four exterior walls. The level of the stone pavement had become uneven over time due to several repairs throughout the mosque's history, but recent work on the courtyard has restored it to its consistent Umayyad-era levels. Arcades (Riwaq) surround the courtyard supported by alternating stone columns and piers. There is one pier in between every two columns. Because the northern part of the courtyard had been destroyed in an earthquake in 1759, the arcade is not consistent; when the northern wall was rebuilt the columns that were supporting it were not.
Three arcades make up the interior space of the sanctuary. They are parallel to the direction of prayer which is towards Mecca, Saudi Arabia. The arcades are supported by two rows of stone Corinthian columns. Each of the arcades contain two levels. The first level consists of large semi-circular arches, while the second level is made up of double arches. This pattern is the same repeated by the arcades of the courtyard. The three interior arcades intersect in the center of the sanctuary with a larger, higher arcade that is perpendicular to the Qibla ("Direction of prayer") wall and faces the Mihrab (Niche in the wall which indicates the Qibla) and the Minbar ("Pulpit").The central transept divides the arcades into two halves each with eleven arches. The entire sanctuary measures 136 meters (446 ft) by 37 meters (121 ft) and takes up the southern half of the mosque complex.
Four Mihrabs line the sanctuary's rear wall, the main one being the Great Mihrab which has located roughly at the center of the wall. The Mihrab of the Companions of the Prophet (Named after the Sahaba) is situated in the eastern half. According to ancient Muslim engineer Musa Ibn Shakir, the latter Mihrab was built during the mosque's initial construction and it became the third niche-formed Mihrab in Islam's history.