There is provided a keyboard structure capable of preventing a fingernail of a user from being inserted between key tops and achieving uniform illumination without illumination leakage. A key top body portion (120a) and an upper sheet (120b) are integrally formed to form a key top (120) and a flange portion (120d) is formed by protruding the upper sheet (120b) from the key top body portion (120a) toward an outer circumferential direction. A frame (122) is disposed between the adjacent key tops (120) and a gap is closed by the flange portion (120d) of the upper sheet (120b) and a flange portion (122a) of the frame (122).