A method for saving power of UE and a device. The method includes, when determining that downlink data to be sent to UE exists and that the UE is in a power saving mode, recording an event that the downlink data to be sent to the UE exists when the user equipment (UE) is in a power saving mode; and sending, when receiving a tracking area update (TAU) request initiated by the UE, an indication message to the UE, where the indication message is used to indicate that the downlink data to be sent to the UE exists when the UE is in a power saving mode so that the UE obtains the downlink data after setting up a data bearer.