The general law of the high salinity water surface evaporation was obtained by water surface evaporation experiments of different salinity EФ20 evaporator at the Changji Groundwater Balance Test Station, Xinjiang. By comparatively analyzing the data, we found that under the same external environment condition, there is a negative correlation between high salinity water surface evaporation and salinity, that is to say, the higher the salinity, the more weaker water surface evaporation, on the Contrary the more stronger water surface evaporation. This is mainly due to the attraction effect of salt molecules to water molecules in the salt water. According to the experimental data, functional relationship between the water evaporation and the salinity was fitted out, and the conversion coefficient of high salinity water surface evaporation was calculated.