The Argan is a multipurpose tree, endemic of South-west of Morocco and Algeria. It populates the Sahara and gives it a very particular physiognomy which is that of the sparse forest. The argan forest is a patchwork of species occupying distinct environmental niches across the Hamada of the South-west region of Algeria. It covers a region characterized by the aridity of the climate and extreme xericity with geological and pedological diversity that are the source of the broad range of magnificent landscapes (Hamada, wet-lands, escarpments, wadis, Regs, mountains). The association of plants with landscapes, reveals an environmental heterogeneity influencing the richness in species and allowing a dynamic and development of a diversified floristic cover mainly xerophilic and thermophilic. The originality of its flora is as-cribed to the presence of Saharo-sindian elements, Mediterranean and en-demic. This particular diversity is due to its biological characterization, sys-tematic and phytogeographic. Unfortunately, this ecosystem and its poten-tial for biological resources are today highly threatened and face degradation from disturbances and uncontrolled exploitation of the plant environment by anthropogenic activities, that requires the development of a preservation strategy. Our work emphasizes the importance of this genetic heritage and its original ecosystem, where the preservation must be secured through the establishment of a strict protection system of species throughout their natu-ral range.