A method for controlling a Bluetooth device for power conservation includes the steps of: establishing a Bluetooth link; controlling the Bluetooth device to enter sniff mode; handling a sniff anchor point after wakeup preparation and before sleep preparation; and handling a wakeup operation between the wakeup preparation and the sleep preparation. The wakeup operation is a BLE (Bluetooth Low Energy) operation or a Wi-Fi operation. The wakeup/sleep preparation can be also done as few times as possible in the invention such that the power consumption of the Bluetooth device is effectively reduced.