Abstract: In order to study the relationship between the sound and the flow rate of the nozzle spray state, the sound signal collection system is used to collect the sound of the nozzle spray, the Fast Fourier Transform（FFT） is performed on the collected sound signal, and the Power Spectral Density（PSD） is calculated, calculate the in-band power, and analyze the correlation between the flow rate and the acoustic signal, and finally get: The nozzle is located at a position 6 cm directly in front of the center of the disc array, and the resulting noise of the sound data is determined to be the optimal position with the smallest noise. Afterwards, through the curve fitting toolbox, a normalized fitting curve of power energy and nozzle flow was established. The Sum of Squared Errors（SSE）was 0.865, and the standard deviation Root Mean Square Error（RMSE）was 0.93. These results demonstrate the feasibility of accurately estimating the nozzle flow rate based on acoustic signals.