The present invention provides an illuminated keyboard, including a light guide backplate and a plurality of keys connected to the light guide backplate. The light guide backplate of the present application is made of a light guide material and configured to transmit and project light rays to the keys. A printed circuit layer is formed on the light guide backplate and includes a plurality of conductive switch contacts. Each key includes a key cap, a connection member, and a support member, and the support member has a conductive contact. When the key cap is pressed, the conductive contact of the support member moves downward to trigger a conductive switch contact of the printed circuit layer to generate a switch signal. In the present application, a light guide backplate provides functions, such as guiding light, a function of printed circuit layer, and connecting a key, so as to reduce thickness of the illuminated keyboard.