Abstract: In this study, an electrical model of E. coli a rod shaped bacterium causing diarrhea through food contamination, is developed using numerical methods to analyse the effects of electric field on it. The critical electric field intensity (Ec) of prolate cell model is calculated both analytically and numerically. The results show that the maximum Ec is obtained for cells oriented parallel to the applied field. The effect of product and microbial factors on Ec is also analysed. The results show that electro-permeabilization is not only a function of cell orientation, but also of product factors and microbial factors.