A double-component mathematical model of droplets' evaporation was developed. Programming with Matlab 6.5, droplet evaporation process in high temperature airflow was calculated. The evaporation rules of droplets were gained. The simulation results were consistent with experiments. Double-component droplet evaporation doesn't follow the2law. Because the evaporation of ethanol was faster than water, evaporation of droplets becomes lower with ethanol concentration of droplets decreasing. The higher the air temperature, the greater the flow velocity, the droplet evaporation time is shorter and the faster the droplet evaporation.