Like many countries around the world, Morocco is facing problems with water supply due to increasing demand and the decrease in conventional resources. To address water shortages, Morocco has long been utilizing non-conventional water resources, such as wastewater reuse and desalination. Initially, desalination was limited to the southern and coastal regions, but it has gradually expanded to the central areas. In many regions of Morocco, the salinity of brackish water significantly exceeds acceptable standards. In Tagounite (located in the southern region of Morocco), where this study was conducted, the salinity of brackish water often exceeded the Moroccan standards, particularly in terms of chloride and sodium content. This contamination is primarily attributed to saline intrusion. The aim of the current study was to evaluate the performance of nanofiltration (NF) for desalinating brackish groundwater in Tagounite and to compare the results with those of reverse osmosis (RO). The desalination process was monitored by assessing performance parameters such as permeability, salinity, chloride, and sodium levels. Several configurations were tested to optimize the process. According to the results, NF membranes demonstrated the potential to produce water of satisfactory quality with high permeate fluxes compared to reverse osmosis.