In this paper, E. coli as experimental subjects ，by changing the input voltage, bacterial concentration, turbidity and pH to study the impact that the use intense white light on the inactivation of E. coli in medium surface. The results showed that: light pulses had a strong effect on lethal E. coli, with the input voltage increasing, the inactivation rate increased. The input voltage is 2500v as an appropriate experimental condition, that satisfy both conservation of energy and a better inactivation .The inactivation rate and the logarithm of livability of E. coli rising with the bacterial concentration increasing, when the light flashes six times, the medium surface almost be killed. Turbidity affect to the inactivation of E. coli, with the turbidity increasing, the effect of the inactivation gradually weakened. When ph was changed, the impact of pulsed light on E. coli inactivation was less .The effect of inactivation achieve the best level when pH was 6.