A method of performing a discontinuous reception (DRX) operation by a user equipment (UE) is provided. The method includes receiving bandwidth part (BWP) configuration information and DRX configuration information, configuring a duration of a timer for the DRX operation, based on the BWP configuration information and the DRX configuration information, and controlling the timer to perform the DRX operation, based on the configured duration, wherein the timer for the DRX operation is controlled before the timer is stopped or expires.