A method for controlling a refrigerator includes starting water supply to an ice making device in a refrigerator. The ice making device includes a flow sensor configured to detect water supply flow to the ice making device by using a pulse value according to rotation of an impeller. The method also includes operating the flow sensor to detect a pulse value, determining whether the pulse value has reached a target pulse value within a preset time, and, based on a determination that the detected pulse value has not reached the target pulse value within the preset time, determining that water supply to the ice making device is in a low water-pressure state and performing a water supply control process according to the low water-pressure state.