A motor vehicle seat is provided with a backrest which can be pivoted from a substantially upright position of use into a substantially horizontal position of non-use. The backrest includes, but is not limited to a wing rest which in the position of non-use of the backrest can be pivoted from a lower armrest position of non-use about a pivot axis extending in seat direction into an upper armrest position of use to form an armrest. The wing rest includes, but is not limited to a support part as well as an upholstery part and between the support part and the upholstery part a height adjusting device for the height adjustment of the upholstery part relative to the support part is arranged.