A key module includes a keycap, an indicator light source, a first backlight source and a second backlight source. The keycap includes an indication area and a character area. The indicator light source is configured to emit an indicating light of a first color toward the indication area. The first backlight source is configured to emit a first backlight of the first color toward the character area. The second backlight source is configured to emit a second backlight of a second color toward the character area, wherein the second color is different from the first color. As a result, the key module could display the light of different colors based on different operations, thereby being distinguishable from the color of the light emitted by the adjacent key module.