The invention discloses a method for preparing macromolecular adsorbents with large specific surface area by means of step-by-step suspension copolymerization pelletization by the aid of sol-gel procedure of vinylsilane coupling agents. The method mainly includes steps of (1), carrying out step-by-step suspension copolymerization on the vinylsilane coupling agents, polyethylene aromatic monomers and ethylene aromatic monomers to obtain copolymer beads; (2), extracting pore-forming agents from the copolymer beads and then hydrolyzing and cross-linking the copolymer beads in acid environments toobtain the macromolecular adsorbents cross-linked after sol-gel treatment. The method has the advantages that the method includes simple procedures and is environmentally friendly, secondary cross-linking steps are carried out, and accordingly, reagents such as chloromethyl methyl ether and dichloroethane with high toxicity can be omitted; the compressive properties and the heat stability of themacromolecular adsorbents prepared by the aid of the method can be obviously improved.