Abstract: A non-invasive direct-mapping USB switching device includes a main-controlled microprocessing module connected to a high-impedance module, and the high-impedance module is provided for detecting and monitoring a functional instruction code of a USB device transmitted from a data transmission module, such that a USB connecting module can be used for transmitting the USB data and functional instruction code to detect and monitor the data transmission module when the USB device is connected to the USB switching device. If the data transmitted from the data transmission module is not the required functional code, the non-required functional code (such as the USB data) will be passed, so that the USB device can be connected and communicated with a plurality of computer devices through another USB connecting module and a switching module to achieve a plug-and-play function.