Application identifier management method and device

The present invention relates to the field of Internet and particularly relates to an application identifier management method and device. The method comprises: receiving, by an identifier management device, a request transmitted by the terminal and used to apply a private key of an application identifier; acquiring, according to the request, by the identifier management device, a user identifier and the application identifier; acquiring, according to the user identifier, by the identifier management device, a feature identifier of the user; generating the private key of the application identifier according to the application identifier and the feature identifier of the user; and transmitting the private key of the application identifier to the terminal. In this way, a corresponding relationship exists between the private key of the application identifier and the application identifier; thereby, when the user encrypts communication content via the private key of the application identifier, the counterpart of the communication determines whether the application identifier is acquired by a valid user via a trustable institution by verifying validity of the private key of the application identifier, thus reducing leaking risk of user private data and ensuring security of the communication content.