Based on the abstraction of network resource,network virtualization can solve the problem of the rigid structure and poor extensibility of network.Virtual network mapping is the mechanism of mapping the virtual network requests from the user layer to the physical layer with multiple constraints such as CPU capability,link bandwidth and so on.In order to help the virtual network be mapped more efficiently,the balance of node's load is concerned,and the feedback mechanism of the node's load is added to the virtual network mapping algorithm which is based on the principle of proximity.Moreover,the occupied rate of link resource as an evaluation index in k-shortest path algorithm is proposed so as to disperse the link pressure.Because the proposed scheme prefers to choose the less occupied physical link,it will take less time to complete the resource mapping with higher success rate,which strongly improves the efficiency of virtual network mapping.