Cedrus atlantica, the Atlas cedar, is a species of tree in the pine family Pinaceae, native to the Rif and Atlas Mountains of Morocco (Middle Atlas, High Atlas), and to the Tell Atlas in Algeria. A majority of the modern sources treat it as a distinct species Cedrus atlantica, but some sources consider it a subspecies of Lebanon cedar (C. libani subsp. atlantica).
Fully grown, Atlas cedar is a large coniferous evergreen tree, (rarely 40 m) tall, with a trunk diameter of . It is very similar in all characters to the other varieties of Lebanon cedar; differences are hard to discern. The mean cone size tends to be somewhat smaller (although recorded to 12 cm, only rarely over 9 cm long, compared to up to 10 cm in C. brevifolia, and 12 cm in C. libani), though with considerable overlap (all can be as short as 6 cm). The Cedrus atlantica leaf length (10–25 mm) is similar that of C. libani subsp. stenocoma, on average longer than C. brevifolia and shorter than C. libani subsp. libani, but again with considerable overlap.
Atlas cedar form forests on mountainsides at , often in pure forests, or mixed with Algerian fir - Abies numidica, Juniperus oxycedrus, holm oak - Quercus ilex, and Acer opalus. These forests can provide habitat for the endangered Barbary macaque (Macaca sylvanus), a primate that had a prehistorically much wider distribution in northern Morocco and Algeria.
Currently, Morocco has the highest total surface of Atlas cedar in the world, and it forms vast forests in the humid zones of the country, around the Middle-Atlas range, the oriental and Northern High-Atlas range, and in the Western and Central Rif mountain range. The current total area is around 163,000 hectares, of which around 115,000 hectares (80%) are situated in the Middle-Atlas mountains. The species is in danger from human use, wood harvesting and fires. Data that go back to 1927 show higher number of Atlas cedars (more than 150,000 hectares) in the Middle-Atlas mountains only.