The laser-induced plasma sound waves during the high-power laser and matter interaction in liquid are investigated by experiments. By the PZT hydrophone,the laser-induced plasma sound waves at different conditions are measured. And the signals of sound waves are analyzed based on FFT. The investigation results show the distribution of laser-induced plasma spectra and the frequency peak have no relation to the energy of the laser,the attenuatioin properties of the laser underwater and the target underwater.