The present invention provides technology that can efficiently guide light to the interior of a key sheet and prevents light from leaking from the circumferences of key tops. A key sheet has a light-shielding dark print layer, on the rear surface of a base sheet, that is a cured body of a coating liquid that is not dissolve to the surface of the base sheet, and also has a smooth surface between the base sheet and the dark print layer. The invention can make light transmitting in the base sheet hard to enter the dark print layer so that the light can be efficiently guided in the base sheet, and also can prevent light from transmitting through the base sheet by blocking the light.