An identity information processing method for operating in a communication network in which a terminal is connected to a second network element connected to a first network element (NSFF) both of which belong to an operator security domain, the second network element being connected to a session management network element of a network slice (NS-2) to which the terminal desires access and which belongs to another domain different from the operator security domain, wherein the method comprises: determining, by the second network element, whether to hide first identity information of the terminal; and when the second network element determines to hide the first identity information of the terminal, hiding, by the second network element, the first identity information to obtain second identity information, and sending, by the second network element, the second identity information to the session management network element of the network slice (NS-2) to which the terminal desires access; wherein before the determining, by the second network element, whether to hide first identity information of the terminal, the method further comprises: receiving (405, 505), by the second network element from the first network device (NSSF), indication information, wherein the indication information is used to indicate whether the network slice (NS-2) to which the terminal desires access is managed by an operator; or the indication information is used to indicate whether to hide the first identity information of the terminal; or the indication information is used to indicate whether the domain to which the network slice (NS-2), to which the terminal desires access, belongs and the operator security domain belong to a same security domain; and the determining, by the second network element, whether to hide the first identity information of the terminal comprises: determining, based on the indication information, whether to hide the first identity information of the terminal. determining, by the second network element, whether to hide first identity information of the terminal; and when the second network element determines to hide the first identity information of the terminal, hiding, by the second network element, the first identity information to obtain second identity information, and sending, by the second network element, the second identity information to the session management network element of the network slice (NS-2) to which the terminal desires access; wherein before the determining, by the second network element, whether to hide first identity information of the terminal, the method further comprises: receiving (405, 505), by the second network element from the first network device (NSSF), indication information, wherein the indication information is used to indicate whether the network slice (NS-2) to which the terminal desires access is managed by an operator; or the indication information is used to indicate whether to hide the first identity information of the terminal; or the indication information is used to indicate whether the domain to which the network slice (NS-2), to which the terminal desires access, belongs and the operator security domain belong to a same security domain; and the determining, by the second network element, whether to hide the first identity information of the terminal comprises: determining, based on the indication information, whether to hide the first identity information of the terminal. receiving (405, 505), by the second network element from the first network device (NSSF), indication information, wherein the indication information is used to indicate whether the network slice (NS-2) to which the terminal desires access is managed by an operator; or the indication information is used to indicate whether to hide the first identity information of the terminal; or the indication information is used to indicate whether the domain to which the network slice (NS-2), to which the terminal desires access, belongs and the operator security domain belong to a same security domain; and the determining, by the second network element, whether to hide the first identity information of the terminal comprises: determining, based on the indication information, whether to hide the first identity information of the terminal.