The invention provides a
fan noise detection method which is suitable for a
machine shell provided with a fan and a plurality of hard disk slots. The method comprises the following steps: taking a plurality of hard disk slots as target hard disk slots in turn, and executing the following steps: inserting an agent hard disk on which a
microphone is arranged into the target hard disk slots, obtaining a critical working period of a fan corresponding to the target hard disk slots, and when the fan operates in the critical working period, measuring by using the
microphone to obtain a
time domain sound pressure level, and converting the time-domain
sound pressure level into a frequency-domain
sound pressure level, taking the frequency-domain sound
pressure level as one of a plurality of frequency-domain sound pressure levels corresponding to the plurality of hard disk slots, and taking a plurality of maximum values of the plurality of frequency-domain sound pressure levels at a plurality of frequencies as a
system sound pressure limit
frequency spectrum, and obtaining and outputting a single
fan noise spectrum according to the
system sound pressure limit spectrum and the number of the fans.