Given the high environmental degradation of Haiti, a study based on the structural and demographic characterization of forest species with burnt crest, 4th communal section of Mirebalais would reveal of paramount importance for the conservation of biodiversity and the mitigation of climate change. climatic. To do this, a dendrometric inventory was carried out through plots with a fixed surface or quadrats of 100 m x 100 m systematically placed on transects. A total of 15 plots were surveyed for the study. Trees 3 cm in diameter were measured at 1.30 m (DBH) and at 30 cm for multi-stemmed shrubs. Trees <3 cm in diameter were considered regenerating. In fact, the total height was measured by the pointing method with a clinometer. The nomenclature used to classify species and families is APG IV. The results showed that the study area has a partial species richness of 40 species distributed in 39 genera and 24 families. The floristic analysis showed that the fabaceae family was the most representative with 11 species.