Abstract: The study of cork oak from the national park of Teniet El Had aims to identify the structure of the stands and the spatial distribution of the stems. So, 30 rectangular plots of 5 a were installed during the year 2013 distributed uniformly in the forest. The spacing of the stems and crowns shows that the area of the cork oak crown decreases in the mixed stands relative to the total height which increases. This is due to competition imposed by other species (Cedrus atlantica, Quercus fagenea). Moreover, in pure stands where the density is less important, the diameter of the crown increases and the total height becomes less important.