Provided are a method for keeping, by a user equipment (UE), a first dual connectivity (DC) configuration in a wireless communication system. The method may include: receiving information for validation of a DC configuration, from a network, wherein the DC configuration includes the first DC configuration and a second DC configuration; determining whether or not the first DC configuration is valid in a radio resource control (RRC) resume procedure, based on the information for validation of DC configuration; if the first DC configuration is valid, keeping the first DC configuration in an RRC resume procedure; and releasing the second DC configuration before initiating the RRC resume procedure.