The brake system of a mine hoist is the key component and the last barrier to ensure the safe operation in a mine. Based on the vibration and the sound signals of a test brake system, this paper studied the characteristics of the signals and the relationship between both the signals and tries to propose a new fault diagnosis method for the brake system. First, the vibration and sound signals of the test set-up under different braking conditions at different brake disc rotation speeds were collected. Then, the vibration and sound signals were filtered and reduced by the wavelet packet, and the reconstructed signal eigenvalues were extracted. The results showed that the characteristics of vibration and sound signals in fault state and normal state can be drawn. It shows the combined fault diagnosis method based on vibration and sound signals can see a wide application to the fault diagnosis for mine hoist brake system. [ABSTRACT FROM AUTHOR]