Suspension polymerization for the droplets of the mixture with monomers, solvent, initiator in water phase with a dispersant PVA was carried out. During the polymerization the molecular weight increasing resulted in the phase separation in the droplets, and a hollow structure was formed. The influence of the hollow structure of the content of the crosslinking agent (DEGDA) and the solvent was discussed. The hollow microspheres prepared in the present study were characterized by optical microscopy (OM), scanning electron microscopy (SEM), particle size analyzer and differential scanning calorimeter (DSC). (c) 2007 Published by Elsevier Ltd.