Abstract: There is described a hand-held game machine including a box which is rectangular when viewed from above, a built-in battery, a game control section driven by the power supplied from the battery, and a flat display. In the game machine, the flat display is arranged substantially in the center of the surface of the box; a key entry switch is provided on one side of the longitudinal center line of the flat display; and one end of a loop string is connected to at least one corner of the box on the same side as that on which the key entry switch is provided, wherein the length of the loop string is set so that the player can place his fingers at the operating position of the key entry switch while the loop of the loop string is wrapped around at least the flat portion of his hand.