PROBLEM TO BE SOLVED: To mechanically regulate noise generated from an expandable actuator of a steering device using a feed screw mechanism, and expansion/contraction of the actuator by the external force. SOLUTION: When a motor 36 is driven, the rotation of its rotary shaft 45 is converted to the expansion/contraction of an output rod 33 by a feed screw mechanism 39, and the toe angle of wheels connected to the output rod 33 is changed. When the motor 36 is stopped, and the toe angle of the wheels is kept, a thrust receiving flange 74 integrated with a male screw member 95 of the feed screw mechanism 39 is elastically supported in the axial direction with respect to a housing 32 by a repulsively urging means 113 composed of a coned disk spring to prevent generation of any play. Any unexpected expansion/contraction of the output rod 33 is prevented, and unstable toe angle of the wheel or noise generation can be prevented. In addition, it is unnecessary for preventing any unexpected expansion/contraction of the output rod 33 by running the holding current in the motor 36, and there is no problem wherein the power consumption of the motor 36 is increased. COPYRIGHT: (C)2010,JPO&INPIT