The invention relates to a disc type permasyn motor for an electric car hub, which comprises a fixed mandrel, a rotor outer casing and a stator armature disc, wherein the rotor outer casing is supported on the fixed mandrel; the stator armature disc is fixedly connected with the fixed mandrel. The left and right sides of the rotor outer casing are symmetrically fixedly connected with parallel magnetic steel discs. A circular air gap of which the cross section is in a rectangle shape is formed between the magnetic steel discs. The stator armature disc is arranged in the circular air gap and is provided with an outgoing line. The stator armature disc has no core, and is directly formed by injection molding. The magnetic steel disc adopts a Halbach type permanent magnet array structure. The invention adopts the stator armature disc without a core for direct injection molding, and the magnetic steel disc with the Halbach type permanent magnet array structure, therefore the motor can greatly enhance power density of the motor, decrease the wear and tear of the motor and has the advantages of small volume, compact structure, stable low-speed running, good controllability, light weight, small vortex consumption of the rotor, small rotating inertia, large power density, small electromechanical time constant and the like.