A keypad structure includes a circuit board, a reflecting plate, a second light guide plate, a second light guide plate, a shading strip, a first light guide plate, an elastic layer, a keypad module and a light source module. A shading strip is provided for attaching the second light guide plate to the first light guide plate. A hole at an overlapped position of the first and second light guide plates is provided for exposing the first light guide plate. A light emitting element of the second light guide plate is lit to project a single-color light onto a corresponding keypad. When the light emitting element of the first light guide plate is lit, different color lights are produced, such that a light transmission effect of single-color light or mixed multiple-color light occurs at the surface of the keypad corresponding to the first light guide plate.