In this paper, we propose an electronic ordering and payment system with embedded devices to improve a conventional manned ordering and payment method using a POS system for quick and easy ordering and payment. Embedded devices as thin clients of the proposed system can be placed on each table, and a user can choose a menu and can check his payment from the screen easily. After a user completes an order, the ordering message is transferred to server for preparing the chosen menu at a shop counter or a cooking place in a restaurant. The proposed system also provides various multimedia contents such as advertising information to users during wait time. Finally we successfully verified the feasibility and the effectiveness of the proposed system by conducting an experiment of ordering and payment checking with several embedded client systems connected to a server system. The proposed system can be applied to an unmanned ticketing or dispenser system, an information kiosk and a guidance robot.