To provide a structure for mounting a skin material for a seat, in which a cushion pad is arranged on a frame part, in which a surface of the cushion pad is covered with the skin material, and in which the skin material can be mounted even on the thin cushion pad.

An elastically openable locking part 8, which is formed in V- shape having an opened end, is provided at a place corresponding to each of mounting places of the skin plates 4 in the frame part 2; and a wedge-shaped hook material 9, which is fixed to the mounting place of the skin material 4, is pushed for engagement into the locking part 8.