To provide a steering device having a variable gear ratio unit and a power assist actuator which is miniaturized and capable of enhancing the degree of freedom in mountability on a vehicle.

The steering device has a variable gear ratio unit 5 in which sun gears 5a, 5a of a first planetary mechanism A connected to a column shaft 2 and a second planetary mechanism B connected to an intermediate shaft 14 are symmetrically arranged and connected by a member 5e, a variable gear ratio control motor 6 connected to a ring gear 5c of the first planetary mechanism A, and a power steering motor 11 connected to the member 5e in the middle of a steering transmission system (the column shaft 2, the intermediate shaft 14, a pinion 15, a steering rack 16, and a tie rod 17) to connect a steering wheel 1 to a turning wheel (a front wheel) 18.

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