This study is devoted to the analysis of psammophile of coastal dunes of the region of Tlemcen. The interpretation by the factor analysis of matches (A. F. C.) has allowed us to individualize classesÂ phytosociologique different. The colonize psammophile, par excellence, the embryonic dunes. Some species colonize the dunes vivid. Finally, other occupies the dunes the most advanced and laid down. Using the data and phytosociologique phytodynamiques, we were able to understand the evolution of this vegetation, and its diversity.