A break detection device includes an extraction unit (22), an extraction unit (23), a detection unit (24), and a determination unit (26). The extraction unit (22) extracts, from an output signal from a sensor, a vibration component in a specific frequency band. The extraction unit (23) attenuates, from the vibration component extracted by the extraction unit (22), a steady vibration component and a progressively increasing vibration component to extract a determination signal. The detection unit (24) detects, on the basis of the determination signal, occurrence of an abnormal variation in the output signal from the sensor. The determination unit (26) determines whether or not a rope has a broken portion.