Embodiments of the present application relate to a method, a system, and a computer program product for authenticating a service. A method for authenticating a service is provided. The method includes receiving a first service request from a first terminal, generating a first link address that is used to link to an access location based on the received first service request, determining a preset terminal identifier corresponding to a second terminal, the preset terminal identifier being a terminal identifier preset by the user, sending the first link address to the second terminal, receiving a first link request, determining an issued terminal identifier based on the first link request, comparing the determined issued terminal identifier with the preset terminal identifier of the second terminal, and performing a next processing operation on the first service request based on the comparison result.