Effects of high frequency spark plasma discharge as a time efficiency method in order to softening the natural hard water has been investigated experimentally. A very hard water sample with 331 +/- 19 mg/l of CaCO3 hardness was used. The current and voltage of each spike was about 9.6 A and 3.5 kV respectively at 16 kHz frequency with 35 mu s pulse width. Hard water was treated for 2, 4, 6, and 8 min. The concentration of CaCO3, Ca2+ ions, Mg2+ ions and pH as well as water conductivity was controlled before and after treatment. The concentration of CaCO3 dropped by 70%, after 8 min treatment. During the treatment, the pH had a fluctuation about 1.5 and finally remained in neutral state. Also the elemental composition, crystalline structure and morphology of the precipitates were identified. Molecular dynamics simulation revealed that the ozone and hydroxyl play important roles in the softening of the hard water.