Abstract: In order to study the cavitation-induced noise characteristics of a single-blade centrifugal pump and to accurately determine the cavitation process, cavitation tests were carried out by building a test rig to analyze the cavitation characteristics of the pump under rated operating conditions. Experimental noise studies were carried out on single-blade centrifugal pumps under three operating conditions, namely, normal cavitation, incipient cavitation and severe cavitation. The noise signals at the inlet and outlet of the centrifugal pumps were collected by hydrophones to differentiate between flow-induced noise and cavitation-induced noise, and the inlet and outlet noise signals were analyzed on a time-frequency basis. The results of the study show that the cavitation-induced noise characteristics of single-blade centrifugal pumps are mainly concentrated in the variation of the low-frequency band clutter signal at the inlet end, while the noise signal at the outlet end has no obvious characteristics. Analyzing of the noise signal enables a more precise localization of the cavitation state of the single-blade centrifugal pump, and wavelet analysis can accurately distinguish between cavitation-induced noise and flow-induced noise. Under different cavitation numbers, there are different in the EMD energy entropy value of the inlet noise signal, and the EMD energy entropy value can be used as a valid characteristic parameter to distinguish different operating conditions of centrifugal pumps.