The utility model relates to a novel taper bushing matched with a center hole of an electromagnetic chuck of a surface grinding machine. The novel taper bushing comprises a taper bushing body (2) and is characterized in that the taper bushing body (2) is a circular tube; the inner surface (6) of the circular tube is conical hole-shaped; and a through groove (7) is formed on the circular tube along the axial direction. Tests prove that the electromagnetic chuck can well run after the novel taper bushing is used; and the service life of the center hole of the novel taper bushing is prolonged from about half one year to more than one year, so that the service life of the center hole is obviously prolonged.