A cover member is a detachable cover member of seat. The cover member comprises at least a skin material and a lining material which is positioned on a back side of the skin material, the lining material is a multistory cloth which is bonded on the back side of the skin material through bonding agent, the cover member comprises bonded parts which the bonding agent is adhered and non-bonded parts which the bonding agent is not adhered between the the multistory cloth and the skin material. And, the multistory cloth may be a multistory knitting fabric which is knitted by polyester resin-made threads, the bonded part may be arranged in any one out of a net-likeshape, a dot-like-shape and a checkered pattern, the bonded part may be arranged irregularly et cetera.