A network service scaling method, comprising: receiving, by a Network Functions Virtualization Orchestrator, NFVO, a network service scaling request, wherein the scaling request comprises a deployment flavor identifier used during a network service scaling, the network service comprises an instance of a first virtualized network function and an instance of a second virtualized network function, and the instance of the first virtualized network function and the instance of the second virtualized network function are connected by using an instance of a first virtual link; obtaining, by the NFVO, a deployment flavor of the network service according to the deployment flavor identifier, wherein the deployment flavor comprises a deployment configuration parameter of the network service, wherein deployment configuration parameters indicate requirements on resources; adding, by the NFVO, a new instance of the first virtualized network function according to the deployment configuration parameter, wherein the new instance of the first virtualized network function comprises one connection point; obtaining, by the NFVO, a modification policy of the first virtual link according to the deployment configuration parameter, and generating, by the NFVO, a descriptor of a second virtual link based on the modification policy of the first virtual link and information about the connection point of the new instance of the first virtualized network function; and creating, by the NFVO, an instance of the second virtual link based on the descriptor of the second virtual link, wherein the instance of the second virtual link connects the new instance of the first virtualized network function to the instance of the second virtualized network function. receiving, by a Network Functions Virtualization Orchestrator, NFVO, a network service scaling request, wherein the scaling request comprises a deployment flavor identifier used during a network service scaling, the network service comprises an instance of a first virtualized network function and an instance of a second virtualized network function, and the instance of the first virtualized network function and the instance of the second virtualized network function are connected by using an instance of a first virtual link; obtaining, by the NFVO, a deployment flavor of the network service according to the deployment flavor identifier, wherein the deployment flavor comprises a deployment configuration parameter of the network service, wherein deployment configuration parameters indicate requirements on resources; adding, by the NFVO, a new instance of the first virtualized network function according to the deployment configuration parameter, wherein the new instance of the first virtualized network function comprises one connection point; obtaining, by the NFVO, a modification policy of the first virtual link according to the deployment configuration parameter, and generating, by the NFVO, a descriptor of a second virtual link based on the modification policy of the first virtual link and information about the connection point of the new instance of the first virtualized network function; and creating, by the NFVO, an instance of the second virtual link based on the descriptor of the second virtual link, wherein the instance of the second virtual link connects the new instance of the first virtualized network function to the instance of the second virtualized network function.