The Multiple Use Reserve of Valle Fértil (San Juan province, Argentina) is a protected area with particular climatic features that includes a large segment of xeric environments. It harbors numerous endemic and protected species. Despite the conspicuous presence of a cacti and succulent community in the area, a formal survey of species richness had been lacking. Moreover, as this region has been declared at risk of degradation due to soil erosion driven by high deforestation rates the importance of carrying out biodiversity surveys with interest on conservation raises. During the last decade, and product of several field trips to the Reserve, seven genera of Cactaceae were observed. Thus, we present the first formal list of cacti and succulent species in the Multiple Use Reserve of Valle Fértil gathering relevant information for scientific and conservational purposes.