A concave notch portion (104, 105) to which an interference body (110) is fitted is formed in an interference region with the interference body existing in an incorporated portion of at least one side edge portion of an interior trim member (100). A
cushion body (25) made of an elastically deformable material is arranged in a periphery including the concave notch portion (104, 105), and a structure member (21) made of a material which is light and harder than the
cushion body (25) is arranged in the other region than the arranged region of the
cushion body (25) in the interior trim member (100). The
skin member (10), the structure member (21) and the cushion body (25) are integrated by a molding. The invention can provides an interior trim member which can be easily attached to and detached from an incorporated position and is not necessary to freshly assemble ducts for an air conditioner, even in the case that a post or the like interfering at an incorporating time or a detaching time exists in a driver seat, in the rigid interior trim member incorporated in the driver seat of various work vehicle.