Provided are a multi-hardware-system data processing device and information input method thereof, the multi-hardware-system data processing device comprising a first hardware system, a second hardware system, a switcher and a shared device; wherein the second hardware system comprises a second control module for generating a message when the second hardware system requires a user to input the information to be inputted, and a second communication module for sending the message to the first hardware system; wherein the first hardware system is connected to the shared device via the switcher and comprises a first communication module for receiving the message, and a first user interaction module for obtaining an input interface to be used by the user to input the information to be inputted according to the message, obtaining the information inputted by the user in the input interface, and sending the inputted information to the second hardware system via the first communication module; the second control module processes the inputted information. By the invention, it is not necessary to conduct switch when the background hardware system needs information to be inputted.