Cold atmospheric pressure plasma generated at atmospheric air produces high energetic electrons, ions, UV radiations, reactive oxygen, and nitrogen species (RONS) which has a wide range of applications in biomedicine, agriculture, textiles, water treatment, etc. Recently, many researches have been carried out on ozonation through DBD (Dielectric barrier discharge) plasma in water treatment. However, direct plasma treatment on water hasn’t been extensively studied yet. In this study, we examined the change in physical, chemical and biological parameters of groundwater by the means of direct DBD plasma activation. The significant reduction in the concentration of biological parameters such as total coliform and E. coli with increasing treatment time was found. Besides that, DBD plasma also lowered down the concentration of physical parameters such as pH, turbidity, total suspended solids, total dissolved solids, and increased electrical conductivity and dissolved oxygen. In addition, the significant drop in the concentration of chemical parameters such as sodium, phosphorus, and calcium was found along with the reduction in heavy metals concentration such as iron, cadmium, lead, chromium, manganese, and zinc. However, the concentration of nitrite, nitrate, and sulfur augmented gradually. Our results revealed the great ability of direct plasma in water treatment.