The Caatinga is one of the Brazilian biomes that has suffered the most from human intervention, reflecting the most varied activities. In this essay, we seek to discuss the importance of preserving the Caatinga and its importance to the semi-arid ecosystem. Knowledge of the species and their importance to the biome itself makes this essay an important manual for analysing the dominant conditions that determine the distribution of certain species.Thus, studies of the environment in the Northeast, and later in the state of Rio Grande do Norte, have come to the fore and the knowledge included in this book has helped in a way to understand the fundamental importance of understanding the Caatinga for its preservation.