The new monodisperse thermo-sensitive stationary phase was prepared by atom transfer radical polymerization method at room temperature using alpha-bromo-isobutyryl bromide as an initiator, and the organic metal compound formed in the CuCl/CuCl2/Bpy system as a catalyst. The stationary phase was characterized by means of elementary analysis and Fourier transform infrared (FTIR) spectroscopy and evaluated in detail to determine its separability, thermosensitivity, stability and reproducibility. The grafting yield of the N-isopropylacrylamide monomer on the surface of poly (glycidyl methacrylate-co-ethylene dimethacrylate) (P(GMA/EDMA)) beads is 10.4%, and the stationary phase can effectively separate 4-hydroxy benzaldehyde, o-cresol and 4-n-butylaniline by changing temperature. The results showed that the synthesized stationary phase has satisfactory chromatographic properties, thermo-sensitive properties and reproducibility.