Abstract: The present invention relates to a method and system for automatically detecting faults in a rotating shaft. The invention comprises the steps of: acquiring a vibration signal from the rotating shaft by means of at least one sensor; processing the signal acquired by the sensor in the time domain and in the frequency domain by means of a processor, obtaining energy measurements of the acquired signal as a result of said processing; comparing in the processor the energy measurements with previously established energy patterns; and finally determining if there is any fault in the rotating shaft based on the comparison between the energy measurements and the previously established patterns.