PURPOSE: To obtain a plannar body of a carbon fiber composite material that is uniform in radiolucency, has designability and is used for an X-ray medical instrument, by laying a surface material comprising a special material capable of providing designability onto the surface of a prepreg sheet laminate wherein fibers are arranged in one direction, and heating and pressing them.

CONSTITUTION: Sheets each consisting of a thermosetting matrix resin and carbon fibers that are arranged in one direction are laminated, and then a surface material consisting of a matrix resin and a material having a thickness of 0.01W 0.5mm that can provide designability and is selected from a group of a fabric, a knit, a spread roving, a mat and a sheet molding compound that are made up of carbon fiber is laid on the surface of the obtained laminate. Then they are heated and pressed in usual manner to obtain the intended plannar body.