Disclosed are methods of executing a handover related operation in a power saving mode in accordance with handover triggering information. One of the methods of executing handover of a mobile station in a mobile communication system comprises determining an enabled status of at least one handover related operation in a specific operation mode between the mobile station (MS) and a network, receiving control information related to the at least one handover related operation from the net work, entering the specific operation mode, changing the enabled status of the at least one handover related operation in the specific operation mode, and performing the enabled handover related operation in accordance with the changed enabled status and the control information.