SEAT

A seat capable of suppressing wrinkles around an opening of a curved-surface-portion of a skin. The seat comprises: a skin in which a curved opening is formed in the curved-surface-portion; an elastically deformable plate-shaped reinforcing-member that reinforces a peripheral portion of the opening, the reinforcing-member being disposed in a curved state along an inner surface of the curved-surface-portion; and a pressing-member that covers the peripheral portion of the opening in a state where the pressing-member presses the peripheral portion of the opening from an outer surface of the curved-surface-portion. The reinforcing-member has a main-body-portion overlapping with the pressing-ember, and extending-portions respectively extending from side edges of the main-body-portion to a range not overlapping with the pressing-member. A slit is formed in each of the extending-portions. The slits extend in a direction that a portion disposed outside in the width direction of the extending-portion is elastically deformable independently from the main-body-portion.