This study aims to analyze the physico-chemical parameters of 11 water samples to establish a qualitative description of water resources and assess their suitability for agricultural irrigation in the Oued Ansegmir (OAW) catchment area (1060 km²). The study involved the collection and analysis of water samples, focusing on cations and anions. Hydrogeochemical classification diagrams, including trilinear Piper and Scholler-Berkaloff diagrams, were modeled using DIAGRAMMES software. A multivariate statistical method, Principal Component Analysis (PCA), was employed to evaluate the physico-chemical parameters. The Water Quality Index (WQI) was calculated for all samples to provide a comprehensive assessment of water quality. The Schöeller Berkaloff diagram indicated the presence of a sodium chloride facies (S1, S4) and a calcium bicarbonate facies for the remaining samples. The Piper diagram revealed a potassium sulphate-chloride facies and a calcium and magnesium bicarbonate facies. PCA identified two main factors: salinity and ion concentration (PC1), and the distinction between geochemical influences and potential human impacts (PC2). The WQI results showed that 36.4% of the water samples were of good quality, while 63.6% were of poor quality. To the best of our knowledge, this is the first study that examined water quality of OAW for agricultural purposes. Our results clearly indicate the suitability of OAW water resources for agricultural irrigation, while providing essential and relevant information for agricultural practices along Oued Ansegmir.