Recently urban population of the globe surpassed the rural one. It means that the sterilization problem (of drinking and waste water, first of all, but not only) becomes an inherent problem of the civilization, especially for the “homo urbanus”. Population of large cities usually has no access to the primary drinking water resources and has to be content with the reused water.    We prove that utilization of the special high voltage electric pulses for liquid media sterilization is a promising non-thermal method which ensures selective action upon vegetative forms of microorganisms. The method could be applied in food industry, pharmacy, perfumery and cosmetics industry, wine industry, medicine and veterinary medicine, utilities and other spheres.  It is demonstrated that high intensity pulsed electric fields offer the unique possibility of non-thermal action upon vegetative forms of microorganisms in the aqueous medium. Combined - physical and chemical - analyses of the processes, which take place in the applicator after high voltage impulses supplying, made it possible to reveal the mechanisms of pulsed electric field action on the cellular structures in the liquid medium and to optimize the main impulse characteristics: amplitude (electric field intensity), form, duration and repetition rate.   Formation of double electric layer on the electrodes determines the essence of the proceeding phenomena. The auto-stabilizing effect which prevents the breakdown in the aqueous gap was established. Due to this effect - together with the electric impulse special form, preliminary degassing and application of sufficient external pressure - it is possible to ensure application of high specific power (P_max > 1 MW/cm³) and cause poration of cell membranes.   Equivalent electric scheme of the applicator is proposed, which makes it possible to estimate the stage of the process (by means of external electrical circuit parameters measuring).   The summary (resultant) polarization of the liquid medium is presented as the result of different types of polarization:  P_Σ = P_{e -} +  P_i  +  P_dipole +  P_structure +  P_electrolyte      (1)  Electronic polarization P_{e -}  is relatively low (negligible), with the polarization time constant τ  ~ 10^-16 - 10^-14 s. Electronic polarization does not lead to dielectric losses in the alternating field.  Ionic polarization P_i is not characteristic for the medium in question, but anyway, it is relatively small, with characteristic polarization time constant τ  ~ 10^-14 to 10^-12 s . Ionic polarization also does not lead to dielectric loss. For the liquid medium under consideration the ionic polarization can be neglected.  The next three types of liquid medium polarization lead to dielectric losses (dipole polarization P_dipole   with the polarization time constant τ  ~ 10^-13 to 10^-7 s ,  structural polarization P_structure with  τ  ~ 10^-8 to 10^-3 s  and  electrolyte polarization P_electrolyte   with τ  ~ 10^-4 to 10^-2 s), are essential for the treatment process and are taken into consideration.   Microbiological tests confirmed the effectiveness of the specified high voltage electric impulses action upon characteristic aqueous media - fruit juices [1].