To provide a height mechanism, in a seat for a vehicle having a seat suspension device.

In a seat for a vehicle with a suspension device formed such that an upper frame consisting of right and left upper frames 2B and 2A is vertically rockably supported at a lower arm 1 through parallel link mechanisms 30, 31, 32, and 33, a pinion gear 50, a rack 51, elevation links 52 and 53 of which a height mechanism consists are arranged at the upper frame. Mounting bracket 43 and 44 on the seat cushion side are coupled to the elevation links 52 and 53.