Abstract: In order to develop a new method of pesticide application for the protection of diseases and insects in the protected agriculture, the tests for revealing the relationships between the atomization performance and the physical properties of related liquid pesticide. The relationships among the parameters of the air pressure and the airflow, spraying flow rate, spraying drop diameter， effective efficiency, sucking liquid height, and the area of air passing through the mouth of the sprayer etc. were obtained. Moreover, the influence of pesticide viscosity and surface tension on the diameter of spraying drop and the spraying flow rate was discovered. All of the tested results provide the basis for designing the two-phase flow sprayer.