The virtual PC management system includes: a unit which acquires a power on/off state of a virtual machine from a computer via the network and stores it in a storage; a unit which acquires a power on/off state of a computer from the computer via the network and stores it into the storage; a unit which receives a start-of-use request for a virtual machine from the client machine and searches stored data of the storage unit for a computer which is in a power-on state and to which a virtual machine is not allocated, as an allocation candidate; a unit which allocates the virtual machine in accordance with the start-of-use request to the computer of the allocation candidate; and a unit which notifies, via the network, the computer of the allocation candidate of an instruction to turn on the power of the virtual machine.