For this study, geochemical data were examined to determine the main factors and mechanisms controlling the water chemistry and the salinity of low Soummam basin in Algeria. Parameters such as pH, EC, temperature, and major and minor element concentrations for two sampling campaigns at the extreme hydrological regimes were considered. The analytical results obtained were interpreted using in particular the molar ratios Na/Cl, Mg/Ca, SO₄/Cl, B/Cl, Br/Cl, Li/SO₄, and Sr/Ca, as tracers of hydrochemical evolution of water, saturation indexes, and the comparison between the chloride content and the other major and minor elements characterizing the salinization. The results obtained indicate the signature of seawater intrusion in the coastal zone and the influence of gypsum outcrops in the upstream zone.