The object of this paper is to analyze the mechanism for the deformation and breakup ■droplet on mechanical agitation. In this experiment, the droplets which had been subdivided to about 50μ by pre-agitation were still more dispersed in the agitation tank. And the values of activation energy E^* and of frequency factor A were calculated. Each average diameter of drop was calculated and the following results were obtained. 1. The value of activation energy was in the range of 5×10³-5×10⁴ (erg/cm²), when particle size was about 50μ. 2. The value of frequency factor was in the range of 2×10^-3-4×10^-2 (1/sec), when particle size was about 50μ.