PURPOSE: To facilitate the detection of the cause of abnormality, when abnormality of a game machine is generated by the case of abnormality of a game control substrate by constituting the game control substrate so as to be visible from the outside, in a state that the game control substrate is contained.

CONSTITUTION: A game control main substrate 37 is attached to a substrate containing box main body 46, and to its surface 70, electronic parts of a CPU and a ROM, etc., are attached. On the reverse side 72 of the game control main substrate 37, a wiring pattern for connecting each of these electronic parts is provided. On the substrate containing body main body 46, a lighting window 75 is provided, and in a position opposed thereto, a transparent cover body 45 is provided. When light is radiated to the substrate containing box main body 46 from the lighting window 75, a wiring pattern provided on the reverse side 72 of the game control main substrate 37 is visible through the transparent cover body 45. Accordingly, whether the wiring pattern provided on the reverse side 72 is changed or not is confirmed without removing the transparent cover body 45.