A live migration method for a virtual machine passthrough device, includes: performing a register state synchronization method by calling a register state synchronization interface; cancelling a passthrough state of the source virtual machine passthrough device, and migrating the source virtual machine passthrough device to the target virtual machine by iteratively executing multiple rounds of a synchronization operation as following: performing the register state synchronization method by calling the register state synchronization interface to capture a read/write operation on a register of the source virtual machine passthrough device in a migration process, and executing the captured read/write operation on a register of a target virtual machine passthrough device; and performing a DMA dirty page synchronization method by calling a configured DMA dirty page transmission interface, to write data corresponding to a DMA dirty page identified by the source virtual machine passthrough device into a memory of the target virtual machine.