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The study of microbial inactivation using HPEF method under long treatment-s time at static system had significant effect (P<0.01) towards physicochemical properties. In order to increase inactivation rate and to maintain its physicochemical properties, HPEF method was combined with UV which has been proved enable to decrease the total microbe population. The research was objected to obtain information related the frequency treatments (10, 15 and 20 Hz) under UV-HPEF combination toward physicochemical properties and microbiological properties. The statistical analysis was conducted using Complete Randomized Design. The result showed that insignificant difference was occurred among frequency treatments at 10, 15 and 20 Hz. The decreased of total microbe was 30.00; 89.49 and 85.67%, respectively. Inactivation rate at each frequency was 0.15; 0.98 and 0.84 log cycle or 3.49; 22.04 and 19.01 log cfu/ml/hour, respectively; D value was 6.46; 1.02 and 1.19 hour, respectively; while k value was 0.36; 2.25 and 1.94 hour-1, respectively. The best treatment was obtained by HPEF-UV series treatment at 15 Hz.