The present disclosure relates to a pre-5th-Generation (5G) or 5G communication system to be provided for supporting higher data rates Beyond 4th-Generation (4G) communication system such as Long Term Evolution (LTE). Disclosed is method of refreshing a security key in a secondary cell group (SCG) controlled by a secondary node (SN) of a wireless communication system, wherein the network is configured to operate in dual connectivity (DC) mode and further comprises a master cell group (MCG) controlled by a master node (MN) the method comprising: the SN indicating in a first message to a user equipment (UE) that security key refresh is to be performed; the UE generating the refreshed security key and transmitting a second message to the SN, wherein the second message indicates that the security key has been refreshed.