A management device obtains network data of a target network. The network data includes a network topology of the target network and device information of a plurality of network devices in the target network, and the device information includes one or more of interface configuration information, protocol configuration information, and service configuration information. The management device extracts a plurality of knowledge graph triplets from the network data. Each knowledge graph triplet includes two network entities and a relationship between the two network entities. The type of the network entity may be a network device, an interface, a protocol, or a service. The management device generates a knowledge graph of the target network based on the plurality of knowledge graph triplets. The knowledge graph of the target network can be used to visualize the network data.