Oak forests in Algeria are rich in resources and services, playing an important ecological and socioeconomic role. The cork oak (Quercus ilex) is one of the most common species in the Chettaba forest, which occupies an area of 1127 hectares. This study aim to assess the health of this species. The protocols for the crown condition indicator are placed in 13 plots of 0.09 hectares, randomly selected in the forest. The diameter and total height of each tree are measured, as well as the crown condition and stand density. A visual assessment of the crowns is performed following the ICP forests and DEPEFEU protocols. The results indicate that the overall condition of the crowns of the cork oak is a medium with significant defoliation. The crowns of the majority of trees (37.6%) are partially visible with backlighting only, codominant (36.54%), and competing with four sides (35%). More than 83.2% of the trees in the Chettaba forest have gourmets, even healthy trees, but fruiting is almost totally absent. Regarding the color of the crown, the majority of the trees examined show no discoloration. In the current conditions of our research, we can say that the overall condition of the holm oak stands in the forest is a medium, which requires further research on the role of the many probable factors of decline. Therefore, special attention should be given to the preservation of this ecosystem.