Disinfection of coliform and E.Coli in the water has been performed by electrolisis using carbon electrodes with a purity of carbon 99,4% from SEM­EDX analysis. This study was conducted using electrolysis powered electric field by carbon electrode as the anode and cathode. Electrolysis method used variations of the addition of NaCl concentration (1,0 ppm, 1.5 ppm, 2 ppm, and 3.5 ppm at voltage 5 volts and electrolysis time 5 minutes), voltage variations (3 volts, 5 volts, 7 volts and 10 volts for 5 minutes and concentration of NaCl 2 ppm), and time variation (2 minutes, 5 minutes, 15 minutes, 20 minutes at 5V and concentration of NaCl 2 ppm) to determine the effect of the disinfection of bacteria. The number of Coliform and E.coli in water before electrolysis was 190 MPN/100 mL and 22 MPN/100 mL, respectively. The Standards Quality Drinking Water No. 492/Menkes/Per/IV/2010 was zero. After electrolysis with variation of concentration of NaCl the number of coliforms and E.Coli did not match with the standards, while with the voltage variations, the number of coliforms and E.coli in 5V matched with the standards and with the vartiations of time, the number of coliforms and E.coli in 5 minutes matched with the standards. The electrochemical disinfection was not to kill bacteria by the electric field but by the chlorin gas of electrolysis process. 
Keywords :Disinfeksi, NaCl, Electrochemistry, Koliform, E.coli