A vehicle steering system includes: a steering member; steered wheels; a steered shaft; a housing; a fitting bracket that has a first bolt insertion hole; a vehicle body-side member that has a second bolt insertion hole; and a bolt that is inserted through the first bolt insertion hole and the second bolt insertion hole. One of the first bolt insertion hole and the second bolt insertion hole is a long hole. When a reverse input equal to or larger than a predetermined value is applied from a road surface to the steered wheel, the bolt is displaced within the long hole in the lateral direction, causing the fitting bracket to displace with respect to the vehicle body-side member in the lateral direction.