With polystyrene (PS) microspheres as the matrix and glycidyl methacrylate (GMA) and methyl methacrylate (MMA) as monomers, two polymer brushes including a homopolymer brush of PS-PGMA and a block copolymer brush of PS P(MMA-b-GMA) were synthesized via surface-initiated activators regenerated by electron-transfer atom-transfer radical polymerization. Furthermore, a ring-opening reaction between epoxy groups in these brushes and hydroxyl groups in 4-hydroxy-2,2,6,6-tetramethylpiperidinooxy (4-OH-TEMPO) was carried out, consequently obtaining nitroxide polymer brushes of PS-PGMA TEMPO and PS P(MMA-b-GMA) TEMPO. The obtained nitroxide polymer brushes were characterized using a variety of analytical techniques. The nitroxide polymer brush as a supported inhibitor was successfully applied in the synthesis of epoxidized soybean oil acrylate (AESO), showing a good inhibiting effect and easy recyclability. Then the supported TEMPO inhibitor (nitroxide polymer brush) and free TEMPO. inhibitor (4-OH-TEMPO) were combined as a compound-inhibiting system to synthesize AESO. After synthesis, the supported inhibitor was recovered by filtration and the free inhibitor was reserved in AESO to prevent it from gelling in the storage process. AESO with excellent performance and low inhibitor residual was obtained through use of this combined inhibitor.