This application provides an IO request processing method, used in an external device. The external device includes a processor and a first hardware interface, and the first hardware interface is an interface that supports a PCIe protocol. The external device communicates with a physical host through the first hardware interface. The method includes: The processor synchronizes, through the first hardware interface, queue information in storage space of a virtual machine running on the physical host to storage space of the external device, where the queue information includes one or more input/output IO requests; and the processor sends the one or more IO requests to a storage server or a network server for processing. According to this application, all hardware resources of the physical host can be used to provide virtual machine services for users, thereby improving utilization of hardware resources of the physical host.