Hydrodynamic properties of different particles in unary liquid–solid fluidized bed were well studied and are reported in literature. However, till date the same in liquid – solid binary packed fluidized bed has not been studied and no information is available in literature. Presently, it is well known that particles behave differently in a gas –solid packed fluidized bed; than in a unary gas –solid fluidized bed. A series of experiments were conducted to investigate the hydrodynamic characteristics of particles in liquid –solid packed fluidized bed as a function of particle size, fraction of interstitial void volume filled by particles and bed wall temperature. It was found that, like in gas –solid packed fluidized bed; the minimum fluidization velocity of particles in liquid – solid packed fluidized bed is lower than that of particles in conventional unary liquid – solid fluidized bed, but unlike gas – solid system, the minimum fluidization velocity increases with an increase in bed wall temperature. Experimental details and results are discussed in this paper.