An automatic extraction device may include a displacement measuring unit for measuring the distance to a container by transmitting a measurement signal and then generating the measurement value which corresponds to the distance to the container; a control unit for outputting a water extraction signal if the measurement value is included within the predetermined target distance range and if the measurement value is not changed during the predetermined reference time; and a water extraction cock for supplying fluid to the container by opening a water extraction valve if the water discharge signal is input.