LUMBAR SUPPORT DEVICE

Provided is a lumbar support device that can reduce a cost involved. One aspect of the present disclosure is a lumbar support device including a base, a pressure-receiving plate arranged at a seat-front side relative to the base, a hinge mechanism moving the pressure-receiving plate in seat front-rear directions, and a lead screw causing the hinge mechanism to be operable. The hinge mechanism includes a first paddle and a second paddle pivoting about a hinge pin in the seat front-rear directions. The first paddle includes a first pressing portion pressing the pressure-receiving plate toward the seat-front side and a first coupling portion coupled to a lead screw so as to be shifted in a seat-width direction as the lead screw rotates. The second paddle includes a second pressing portion pressing the pressure-receiving plate toward the seat-front side and a second coupling portion rotatably coupled to the based.