Groundwater quality plays a vital role in addressing freshwater demands, especially in semiarid regions with water scarcity. This study focuses on assessing groundwater quality in the Tebessa aquifer system, a primary water source for various needs. The investigation is prompted by challenges like hydric stress, aridity, urbanization, and population growth, which impact water demand and quality. Factors such as intensive agriculture and industrial activities contribute to declining groundwater quality. The study employs the Water Quality Index (WQI) method, which combines multiple parameters to evaluate water health comprehensively. Geographic Information Systems (GIS) technology aids in analysing spatial relationships, crucial for hydrogeological processes. The study incorporates a multiparameter approach to create maps of water quality, with parameters including pH, Total Dissolved Solids (TDS), and various ions. These maps reveal spatial variations and priority classes ranging from 'Excellent' to 'Very Poor' in groundwater quality. The main objective is to enhance understanding of groundwater quality dynamics in semiarid regions and identify management strategies. The Tebessa-Morsott Plain in Algeria serves as the study area, characterized by a semi-arid climate. Field and laboratory investigations were conducted to analyse hydrochemical characteristics. The results show diverse ranges of parameters, indicating alkalinity, salinity, and elevated concentrations of ions. By analysing interrelationships and spatial variability, the study contributes to both scientific understanding and informed water resource management. Geospatial mapping and the generation of a groundwater quality index map illustrate varying levels of water quality across the study area, guiding strategic decisions for sustainable water resource management.