a packing material for liquid chromatography comprising monovinyl aromatic monomer and divinyl or polyvinyl aromatic monomer is disclosed , wherein , in gel permeation chromatography , exclusion limit molecular weight is not less than 1 × 10 3 in terms of standard polystyrene , average particle diameter lies within a rage of 0 . 5 to 50 μm and the constitution rate of divinyl or polyvinyl aromatic monomer in copolymer particles is not less than 60 % by weight , and a method for the preparation thereof is claimed , wherein suspension polymerization is carried out in a mixed aqueous solution containing organic colvent which dissolves whole monomer containing not less than 60 % by weight of divinyl or polyvinyl aromatic monomer in whole monomer by amounts of 50 to 300 % by weight of the solvent to both monomers and does not dissolve the copolymer of these monomers and radical polymerization initiator .