The present disclosure relates to a 5G or pre-5G communication system for supporting a higher data transfer rate beyond a 4G communication system such as LTE. A terminal according to an embodiment of the present disclosure performs the operations of: transmitting a registration request message to a network node; receiving an authentication request message containing information on a security related capability from the network node; verifying the security related capability by using the authentication request message; transmitting a first message as a response to the authentication request message; receiving a security mode command message from the network node; and transmitting, to the network node, a security mode completion message as a response to the security mode command message, wherein the information on the security related capability includes information on a capability related to security between the terminal and the network node.