The invention discloses a method, a system and a device for terminal grade classification, belonging to the field of communication. The method comprises the following steps: an access request of a terminal is acquired; and after the integral verification of the terminal is finished, an access grade of the terminal is classified according to a preset classification strategy. The system comprises aterminal device and a service end device, wherein the service end device comprises a receiving module and a processing module. The invention effectively solves the problem that the PDP access standardis single in the TNC credible access process by leading in credible grade judgment, improves the credible access process and separates the integral verification from security evaluation; and in addition, after a terminal user passes through the integral verification to access a credible network, a network manager can adopt different tracking control schemes, such as the scheme of controlling access authority of resources of different confidentialities and importance, and the like aiming at different users according to safety states of the users.