Viewing operating information of a device is controlled appropriately. A viewing control server has: an identification information manager that acquires, through a network from a manager function that manages one or more devices, device identification information unique to each device, manager identification information unique to each manager function, and customer identification information unique to each customer, and relationally stores the acquired device identification information, manager identification information, and customer identification information; a device information collector that acquires device information, which is operating information of each device, from the manager function through the network; and a viewing controller that identifies the customer identification information according to an operation from an external device, and enables viewing on an external device the device information of a device identified by the device identification information relationally stored to the identified customer identification information.