Atlasaurus is a genus of sauropod dinosaurs from Middle Jurassic (Bathonian to Callovian stages) beds in North Africa.

It is known from a nearly complete skeleton with a skull found at Wawmda, in the Middle Jurassic (Bathonian-Callovian) Guettioua Formation in Morocco's Azilal Province.

The type species is Atlasaurus imelakei, the specific name coming from Arabic عملاق ("eimlaq" or "imelake"), meaning "giant".

[1] A second specimen of A. imelakei, a near-complete tail, was also discovered in Morocco and was pieced back together in Utah after 300 hours of preparation.

[2] Atlasaurus differs from Brachiosaurus relative to the estimated length of the dorsal vertebral column (assuming 12 vertebrae, 3.04 m (10.0 ft)), in having a proportionately larger skull, a shorter neck (with at least 13 cervical vertebrae, shorter and more uniform in length than Brachiosaurus), a longer tail and more elongated limbs (humerus to femur ratio: 0.99; ulna to tibia ratio: 1.15).