The objective of this research was the groundwater quality analysis in the Mygdonia basin in order to contribute to the protection of groundwater quality and the sustainable management of water resources in the study area, which is characterized by intensive agriculture activities. The interval of June and August-September 2014 was selected for measurements to be carried out. More specifically, during these two periods, in situ physicochemical parameters (pH, EC, T) were determined, showing in some cases high temperature values, which may be due to the mixing of the groundwater with geothermal fluids, and alongside water samples were collected from 17 and 26 boreholes, respectively. All samples were analyzed in the laboratory of Engineering Geology and Hydrogeology in the Aristotle University of Thessaloniki for major ions (Ca²⁺, Na⁺, Mg²⁺, K⁺, NO₃^-, SO₄^2-, Cl^-, HCO₃^-) regarding the qualitative groundwater status in the research area. The final conclusions and the spatial allocation for both ions and physicochemical parameters were depicted in maps, created in ArcGIS environment for both June and August-September. Furthermore, Piper and Durov diagrams were created by the use of AquaChem software, in order to define the hydrochemical type of groundwater. In general, the water quality is considered suitable for irrigation purposes. Finally, some recommendations are proposed to protect the quality and improve the sustainability of the groundwater resources of the basin.