In order to study the inactivation effects of electrostatic field of electret films on Bacillus subtilis, a plane-plane electrode system was used to simulate the electrie field of the electret films and the viability of B. sublilis affected by electrostatic field for different applying durations was investigated. It was found that the survival ratio of B. subtilis can be considerably affected by the field and duration. It was also found that the viability of bacillus decreases with the increase of the duration. In addition, the comparative survival ratio (CSR) of B. subtilis decreases to 35% even during a short duration as the applied field reaches an enough high value of more than 15kV/cm. These indieated that the uniform field inactivated the viability of B. subilis availability. Based on the inaction effect of the applied field on the B subtilis, the effectiveness of chared polypropylene films on the inactivation of B. subtilis was measured and discussed.