Reactive oxygen species solution produced by strong ionization discharging plasma was used to kill Escherichia coli by spraying.Several effect factors such as pH value,solution temperature,spraying time and exposure time were observed in this study,and their effects on killing rate of Escherichia coli were discussed and analysed.Results show that the treating efficiency of ROS solution for Escherichia coli is higher in alkaline solution than that in acid solution.The killing rate of Escherichia coli increases while the spraying time and exposure time are longer and the temperature is lower.The effects of different factors on killing rate of Escherichia coli are as follows:spraying time>pH value>exposure time>solution temperature.