Abstract: In order to explore the effects of the electric field processing and dielectric separation on the germination rate and the seedling mass of coated cottons, an electric field processing test was conducted with an arista electrode at a voltage of -16 kV (DC). The results showed that the germination rate and the seedling mass of the cotton seed were significantly improved. In addition, a dielectric separation was performed with an dielectric separator at the different separating voltage, and the results also showed that the germination rate and the seedling mass of the Class A cotton seed significantly increased when the rotating speed of the separating roller was of 20 r/min and the selecting voltage was of -6 kV (DC). It was also found that both the germination rate and the seedling mass of the seed which was firstly processed with the electric field and then separated with the dielectric separator under the above optimum conditions were significantly higher than that of the seed which was solely processed with the electric field or separated with the dielectric separator. It will provide a foundation for developing a new processing and separating device, it has a great significance for agricultural production.