The direct measurement of fine particles size distribution of dispersions or coagulations in liquid is important for water purification, fine particles separation for recycling and mineral processing, as well as the new material production. The nano to micro particle size is usually measured by light scattering method; however, it is difficult to measure at high concentration of suspension. Here, a novel dynamical method by using the interactive force measurement between particles in liquid under electric field is used for measuring distribution of fine particle. Three types of nano to submicron particles, that is well-dispersed nano particles, coagulated nano particles and settled submicron particles, have been measured by interactive force measurement method. The particle size distributions are compered with the size distributions of dried particles measured by TEM or SEM. The well-dispersed nano particle size distribution by interactive force measurement is influenced by the nano size surfactant micelles. The size distribution of coagulated nano particles in water is larger than the result by TEM. On the other hand, the submicron nickel particle size distribution is similar with the one analyzed by SEM.