A network topology management system includes information processing units, storage units, connection units that control connection switching between the information processing units and the storage units, a management unit that manages a network topology consisting of the information processing units, the storage units and the connection units, and an emulator connected to the connection units and to the management unit of the network. The emulator comprises a conversion section that converts first equipment identification information that identifies the information processing units or the storage units into second equipment identification information that is recognizable by the management unit to identify the information processing units or the storage units, and a transmitting section that sends the second equipment identification information to the management unit. The management device has a control section that manages the network topology based on the second equipment identification information.