The invention discloses a radial decoupling taper magnetic bearing with three degree of freedom, comprising an upper taper stator, a lower taper stator , an upper taper rotor, a lower taper rotor, radial stators, a radial rotor iron core, a field coil, a permanent magnet, a stator magnetic conductive ring and a rotor magnetic conductive ring, wherein, the taper stators and the taper rotors are the structure of integral ring, the suction generated between the taper stator and the taper rotor passes through the rotor barycenter to control the translation in the direction z of the rotor; the tworadial stators comprise stator teeth and stator magnet yokes, the two radial stators are arranged orthogonally when being installed, and a radial stator magnetic isolated ring is arranged between thetwo stators to let the magnetic circuit between the two radial channels be mutually decoupling; the suction generated between the radial stator and the radial rotor iron core is used to control the translation in the direction x and y of the rotor. According to the invention, the suction generated between the taper stator and the taper rotor passes through the rotor barycenter, when the rotor rotates, the length of the arm of force of negative stiffness is reduced, so that negative torsion moment is reduced; simultaneously, the two radial channels are decoupling, so that the radial bearing capacity is increased.