An electronic brake motor structure includes a lower housing coupled to a block; a ball screw installed in the center inside the housing and block; a nut member into which the ball screw penetrates to be coupled therewith; a piston coupled to an outer side of the nut member; a hollow shaft coupled to an outer side of a lower part of the piston; a rotor module including a rotor and a magnet, coupled to an outer side of the hollow shaft; a stator module coupled to an outer side of the rotor module; an upper bracket for mounting a first bearing to thereinside; a driven shaft, coupled to an upper part of the ball screw to support the ball screw; a joint member coupled to a bottom of the ball screw with a mounting bolt to support the ball screw and a fourth bearing.