Disclosed is a data processing device, which comprises: an input device for generating first input information; a central processor; an embedded controller, connected to the power supply, the input device and the central processor. When the data processing device is powered on, the embedded controller is adapted to control the power supply to supply power to the input device and the central processor; process the first input information as second information, which can be identified by the central processor; and send the second information to the central processor. When the data processing device is powered off or sleeping, the embedded controller is adapted to control the power supply to supply power to the input device; detect whether a terminal device comprising an operating system is connected and generate a detection result; electrically connect to the terminal device when the detection result indicates that the terminal device comprising the operating system is connected; process the first input information to obtain third input information, which can be processed by at least one program running based on the operating system in the terminal device; and send the third input information to the terminal device. The present invention provides a data processing device and data processing method for solving the inconvenient operations of the traditional handsets and the like terminal devices.