According to the principle of liquid atomization a nozzle for electric mist sprayer was designed. The performance parameters of the liquid nozzle, such as pressure, diameter of nozzle orifice films, droplet diameter and volume, as well as the structure of spray nozzle and principle of the nozzle were analyzed. The test results indicated that the various droplet diameters could be obtained by adjusting the distance between nozzle body from top to bottom part of the installation or replacement nozzles films, or by changing the hole with different angle. When operated in greenhouse it is advised to use nozzle orifice films with φ0.7mm or φ1.0mm and φ1.2mm or φ1.5mm in field or small orchards operations.