System and method for renting out general computing power based on virtual machine

The invention discloses a system and method for renting out general computing power based on a virtual machine. The method and system are used for providing the computing power of a user computer connected to a network outwards through the network. The method and system are based on a virtual machine technique, a restricted virtual machine execution system and a computing task agent are set up on the user computer, the user computer dynamically acquires computing tasks in a computing task server of the network through the computing task agent, a virtual machine instance image including the completion and execution environment of the computing tasks is downloaded in the user computer, the restricted virtual machine execution system sets up a restricted virtual machine instance according to the virtual machine instance image, the restricted virtual machine instance is executed under the control of the restricted virtual machine execution system, and the execution result of the computing tasks is returned to the computing task server on the network. According to the method and system, the user computer can effectively provide the general computing power outwards.