A virtual machine deployment method, comprising: establishing (S110) mapping between a host virtual address, HVA, space for a post-upgrading virtual machine and a host physical address, HPA, space for a pre-upgrading virtual machine according to a mapping relationship between a HVA space for the pre-upgrading virtual machine and the HPA space for the pre-upgrading virtual machine, wherein the post-upgrading virtual machine is deployed on a post-upgrading virtual machine monitor, VMM, and the post-upgrading virtual machine is identical in memory configuration with the pre-upgrading virtual machine running on a pre-upgrading VMM; wherein establishing (S110) mapping between a host virtual address, HVA, space for a post-upgrading virtual machine and a host physical address, HPA, space for a pre-upgrading virtual machine according to a mapping relationship between a HVA space for the pre-upgrading virtual machine and the HPA space for the pre-upgrading virtual machine comprises: determining (S111) a sequence and a sequence number of a page table entry of each of physical memory pages in the HPA space for the pre-upgrading virtual machine; and reversely mapping (S112) each of the physical memory pages to a corresponding virtual memory page of the HVA space for the post-upgrading virtual machine according to a corresponding relationship between the page table entry of each of the physical memory pages and the sequence number. establishing (S110) mapping between a host virtual address, HVA, space for a post-upgrading virtual machine and a host physical address, HPA, space for a pre-upgrading virtual machine according to a mapping relationship between a HVA space for the pre-upgrading virtual machine and the HPA space for the pre-upgrading virtual machine, wherein the post-upgrading virtual machine is deployed on a post-upgrading virtual machine monitor, VMM, and the post-upgrading virtual machine is identical in memory configuration with the pre-upgrading virtual machine running on a pre-upgrading VMM; wherein establishing (S110) mapping between a host virtual address, HVA, space for a post-upgrading virtual machine and a host physical address, HPA, space for a pre-upgrading virtual machine according to a mapping relationship between a HVA space for the pre-upgrading virtual machine and the HPA space for the pre-upgrading virtual machine comprises: determining (S111) a sequence and a sequence number of a page table entry of each of physical memory pages in the HPA space for the pre-upgrading virtual machine; and reversely mapping (S112) each of the physical memory pages to a corresponding virtual memory page of the HVA space for the post-upgrading virtual machine according to a corresponding relationship between the page table entry of each of the physical memory pages and the sequence number. determining (S111) a sequence and a sequence number of a page table entry of each of physical memory pages in the HPA space for the pre-upgrading virtual machine; and reversely mapping (S112) each of the physical memory pages to a corresponding virtual memory page of the HVA space for the post-upgrading virtual machine according to a corresponding relationship between the page table entry of each of the physical memory pages and the sequence number. <EOS>