A processing method for terminal access to a 3GPP network is provided. UE sends an access request message to a core network device on the 3GPP network, and the core network device sends an unauthorized access message to the UE after determining that the UE has no permission to access the 3GPP network. The unauthorized access message includes authentication information of the core network device. The UE performs authentication on the core network device according to the authentication information of the core network device, and executes a corresponding network access policy after authentication on the core network device by the UE succeeds, that is, after the UE determines that a source of the unauthorized access message is authorized.