A registration application support system includes: a registration application device that is included in a first organization and applies for pre-registration for delegation of a right regarding access to a resource to an authorization server; and an existence guarantee device that is included in a second organization and guarantees existence of the first organization, in which: the existence guarantee device includes a giving unit that gives an electronic signature to information that guarantees the existence of the first organization, in response to a request from a terminal used by a member of the first organization; the registration application device includes a transmission unit that transmits a display name of the first organization and the information to which the electronic signature has been given to the authorization server in order to apply for the pre-registration; and the authorization server includes a verification unit that causes the existence guarantee device to verify the electronic signature, and a determination unit that determines whether or not the first organization has a right to use the display name. Therefore, pre-registration for delegation of an access right to a resource is safely and efficiently performed.