To provide an electric power steering device for improving a steering responsive feel during the neutral of a steering wheel by utilizing the reaction force from a turning wheel side for moving a rack shaft in the axial direction without rotating a ball nut.

A driven gear shaft 34 is rotatably supported on a housing 20 by a bearing 35, and the ball nut 23 threaded to the rack shaft 18 via a ball 22 is supported on the inner periphery of the driven gear shaft so as to be relatively movable in the axial direction. An engaging means 45 (45A, 45B) is provided for elastically energizing the ball nut against the driven gear shaft to its axial neutral position. The energizing means is elastically deformed when an input is applied from a road surface to the rack shaft.

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