Aiming at the problem of online monitoring of laser paint removal, an acoustic monitoring experiment platform was built to study the acoustic monitoring technology of the laser paint removal process. Combining surface topography and signal processing, through time domain and frequency domain analysis, a series of characteristic parameters such as the peak value of positive pressure of the sound wave, the duration of the pulse waveform, the cleaning frequency component, the DC component and the frequency of the first spectral peak are found.According to these parameters, the discriminant function is obtained through the stepwise discriminant analysis method.Research shows that the acoustic signal of laserpaint removal can provide effective characteristics information, and the process of laser paint removal can be monitored through the recognition of cleaning characteristics.Acoustic monitoring has further practical potential.