Discharge to sea water is very hard and require considerable high voltage. But specially designed electrode can support plasma discharge to saline water with relatively low voltage. The round-shaped ceramic electrode having a lot of pinhole combined with metallic one was developed. Different types of electrodes were tested by changing number of hole and diameter of hole. The operating conditions of power generator are 5 kV voltages, 10 kHz frequency, 3 micro second pulse width and 5 kW power at 4th generation plasma reactor (4G). During discharge in water, Temperature is increasing and pH decreased lineally. It was obtained that 0.36 decrease of pH and 16 degrees C increase of temperature by 4.5 MJ energy supply at 30 L water vessel. In this plasma condition, the nucleus and electrons are separated and new kinds of components are resynthesized by the intensive movement of the components. Especially chlorine ions can be separated and recombined to residual free chlorine like HOCl, OCl(-). In this experiment, generation of chlorine was observed. It was obtained that 50 mg generation of total residual oxidant by 4.5 MJ energy supply. It was measured by several times repetitions that 0.52 mg-Cl(2)/L could disinfect E. coli till 99.9%. Another unconfirmed radical and oxidants for example, OH and H(2)O(2) can have an effect on microorganism of course (C) 2011 Elsevier B.V. All rights reserved.