To provide a vehicle seat assuring practical application with good easiness to handle, whereby holding approximately horizontally can be generated only by taking out an assist seat from an accommodation box.

The vehicle seat is equipped with a first link 19 and a second link 23, and it is arranged so that the end 23a of the second link 23 is pressed to the end of a second long hole 22 when the assist seat 7 is turned toward outside the accommodation box 5, and also the end 19b of the first link 19 is pressed to the bottom of a first long hole 16, and thereby a leg member 11 is fixed in the vertical attitude to cause an assist seat cushion 8 to be held approximately horizontally.