A rack shaft support device comprising: a support yoke that is arranged in an accommodating portion of a rack housing for accommodating a rack shaft and that moves the rack shaft in a pressing direction toward the pinion shaft in the accommodating portion; a plug that has a plug fixing portion, a plug cam portion, a plug back wall portion and a first restricting portion, the plug fixing portion being arranged across the support yoke from the rack shaft in the accommodating portion and being fixed to the rack housing, the plug cam portion being arranged closer to the support yoke than the plug fixing portion and having a first cam face, and the plug back wall portion being formed across the plug fixing portion from the support yoke, an intermediate cam component that has an intermediate cam body, an intermediate cam portion and a second restricting portion, the intermediate cam body being arranged closer to the support yoke than the plug in the accommodating portion and having an axis extending in the pressing direction, the intermediate cam portion being formed around the intermediate cam body and having a second cam face that contacts the first cam face, and a rotation force generating spring that is connected to the plug and that applies force to the intermediate cam component to cause the intermediate cam component to rotate with respect to the plug characterized by the first restricting portion protruding from the plug back wall portion toward the support yoke; and the second restricting portion protruding from the intermediate cam body toward the plug and facing the first restricting portion in a direction that intersects with the axis of the intermediate cam body. a support yoke that is arranged in an accommodating portion of a rack housing for accommodating a rack shaft and that moves the rack shaft in a pressing direction toward the pinion shaft in the accommodating portion; a plug that has a plug fixing portion, a plug cam portion, a plug back wall portion and a first restricting portion, the plug fixing portion being arranged across the support yoke from the rack shaft in the accommodating portion and being fixed to the rack housing, the plug cam portion being arranged closer to the support yoke than the plug fixing portion and having a first cam face, and the plug back wall portion being formed across the plug fixing portion from the support yoke, the plug fixing portion being arranged across the support yoke from the rack shaft in the accommodating portion and being fixed to the rack housing, the plug cam portion being arranged closer to the support yoke than the plug fixing portion and having a first cam face, and the plug back wall portion being formed across the plug fixing portion from the support yoke, an intermediate cam component that has an intermediate cam body, an intermediate cam portion and a second restricting portion, the intermediate cam body being arranged closer to the support yoke than the plug in the accommodating portion and having an axis extending in the pressing direction, the intermediate cam portion being formed around the intermediate cam body and having a second cam face that contacts the first cam face, and the intermediate cam body being arranged closer to the support yoke than the plug in the accommodating portion and having an axis extending in the pressing direction, the intermediate cam portion being formed around the intermediate cam body and having a second cam face that contacts the first cam face, and a rotation force generating spring that is connected to the plug and that applies force to the intermediate cam component to cause the intermediate cam component to rotate with respect to the plug characterized by the first restricting portion protruding from the plug back wall portion toward the support yoke; and the second restricting portion protruding from the intermediate cam body toward the plug and facing the first restricting portion in a direction that intersects with the axis of the intermediate cam body.