A wiring board including a first rigid wiring board including a conductor and having an accommodation portion, the accommodation portion having wall surfaces, a second rigid wiring board accommodated in the accommodation portion and including a conductor electrically connected to the conductor of the first rigid wiring board, the second rigid wiring board having side surfaces, an insulation layer formed on the first rigid wiring board and the second rigid wiring board, and a metal film having a solid pattern formed directly on a boundary portion formed between the wall surfaces of the accommodation portion and the side surfaces of the second rigid wiring board.