There is provided a network management device (1) including a capacity management unit (10) for managing the capacity in a network to be managed and a storage unit (20) for storing management information. The storage unit stores specification information of entities included in the network, and entity information including information indicative of relationships between the entities. The capacity management unit 10 includes a capacity request acquisition section (11) which receives a generation request of a first entity; reads the specification information about the first entity from the storage unit, and determines whether or not the first entity needs to consume a resource; when it is determined that the first entity needs to consume a resource, identifies a second entity capable of providing capacity consumed by the first entity, based on the entity information stored in the storage unit; and outputs information about the identification result.