Provided are a method and system for protecting virtual network mapping, and a computer storage medium; wherein the method includes that an application layer edits and defines at least one sub-network model based on a network editing request; a network virtualization layer constructs the at least one sub-network model, and integrates the at least one sub-network model into a global network view; and a controller layer respectively maps the at least one sub-network model contained in the global network view into a working device network and a protection device network, and when the working device network has failures, specified conditions are met, and the protection device network has no failure, switches a working mapping relationship of the corresponding sub-network from the working device network to the protection device network.