Polystyrene-poly(ethylene oxide) (PS-PEO) block copolymers form micelles in aqueous solution. When the solution is mixed with a dispersion of polystyrene latex spheres (PSL) in suspension, adsorption of copolymer molecules onto latex particles takes place. The adsorption changes the physical dimension and the surface characteristics, such as zeta potential, of the particles. electrophoretic light scattering is used to investigate the adsorption kinetics by measuring mobilities and mobility changes of PSL in the mixtures. The mobility of PSL is decreased after PS-PEO copolymers adsorption due to surface potential reduction at the shear layer. Analysis of the electrophoretograms reveals that there are several kinetics processes for the surface rearrangement of the polymer chains on the surface after adsorption, depending upon the mixing ratio and the curvature of the PSL particles. On the basis of the present observations a three-step kinetic mechanism is proposed.