Abstract: The unsatisfactory appearance of the dextran beads consists in particle aggreg ation and rough surfaces. The authors prove that the main reason of the particle aggregation is the hydrolysis of the dispersing agent, polyvinyl acetate (PVAc), throgh which the hydro-philicity of PVAc increase and the flocculation tendency of the intermediates of the crosslin-king reaction. Rise in viscosity of the beads as a result of crosslinking could also cause the particle aggregation. The surfaces of beads become rough because PVAc failed to be removed from the surfaces after crosslinking. These problems can be solved through the control of the dispersion and crosslinking temperature, the agitation rate and the feeding manner of the cross-linking agent.