The dispersion and frequency of fluidizing particles and the histogram of pressure fluctuations have been analyzed in a liquid fluidized bed. The effects of particle size(1.0-6.0mm)and liquid velocity(3-14cm/s)on the dispersion coefficient and frequency of fluidizing particles have been determined in a 0.152m-ID×2.5m high Plex-iglas column. The dispersion coefficient and frequency of fluidizing particles exhibit their maximum values with an in-crease in liquid velocity and consequent increase in bed porosity. The maximum particle dispersion coefficient ex-hibits at the bed porosity where the flow transition of particles occurs in the bed.