To prevent folding due to impact when a ceiling lining material for sun roof vehicle is mounted on a vehicle which is generated in a corner part on a rear side of a roof opening conventionally by providing a thermoplastic resin plate between a papery wave-shaped central core and liner paper on a front skin side.

A thermoplastic resin plate 6 is provided between a papery wave-shaped central core 4 and liner paper on a front skin side. Particularly it is preferable to provide the thermoplastic resin plate 6 having the thickness of approximately 0.7 to 1.00mm in a part 7 marked by tilted lines in a corner part of an opening on a line along a rear fringe of a roof opening H. Usually, polypropylene is used as a material of the thermoplastic resin plate 6. Consequently, the initial bending elasticity of a basic material made of corrugated board is markedly improved in the MD direction of the basic material. When this interior material is used as a molded ceiling of a sun roof vehicle, it is possible to prevent impact when it is mounted on the vehicle which is generated in a corner part on a rear side of the roof opening H conventionally and folding due to the application of load.