KVM (Kernel-based Virtual Machine) is a virtual machine based on Intel VT technology and works with QEMU, which provides device virtualization. From the process point of view, this paper focuses on the analysis of the initiative and the running mechanism of KVM virtual machine, based on the analysis, a method of isolating KVM virtual machine is implemented, which makes the KVM virtual machine run on the specified core whenever it’s created or running, and achieves the maximized utilization of processor resources.