Micron-sized silica gel particles were surface-modified with the coupling agent γ-mercaptopropyl trimethoxysilane (MPMS), and the modified MPMS-SiO2 particles with surface bonding of mercapto groups were obtained. In non-aqueous solvent dimethylformamide (DMF), a surface-initiating system -SH/AIBN was constructed by the mercapto groups on MPMS-SiO2 and azodiisobutyronitrile dissolved in the solution, and the graft-polymerization of methacrylic acid (MAA) in the non-aqueous solvent was realized, obtaining the grafted particles PMAA/SiO2. The grafted particles were characterized, and the effects of the main factors on the graft-polymerization of MAA examined. On this basis, the adsorption of grafted particles PMAA/SiO2 for ferulic acid as a phenolic acid compound with hydrogen bonding was tested. The results show that the -SH/AIBN can smoothly initiate the graft-polymerization on silica gel particles in a non-aqueous solvent, the suitable temperature is 75℃, and appropriate content of AIBN 1.5% of the monomer mass. There is very strong hydrogen bonding including the strong and multi-site common hydrogen bond and π type hydrogen bond, leading to a strong adsorption ability of the grafted particles PMAA/SiO2 for ferulic acid at 266 mg/g. In the protonic solvent, methyl alcohol, the competitive adsorption of the solvent on the grafted particles PMAA/SiO2 makes the adsorption capacity of ferulic acid to decrease, and raising the temperature also makes the adsorption capacity of ferulic acid to decrease.