The coincidence relation between laser pulse energy and hydroacoustic specialty was analyzed.Achromatic aberration lens system,Nd∶YAG laser which pulse energy is adjustable,a hydrophone and a digital oscilloscope are used to generate and record laser induced hydroacoustic signal.The conclusions as follows:First,when the pulse energy increases within the range from 70mJ to 300mJ,the peak pressures of laser-induced hydroacoustic linearly increase,the interval between plasma expanding induced hydroacoustic and bubble collapse induced hydroacoustic increase correspondingly.Second,the peak pressure of bubble collapse induced hydroacoustic is higher than that of plasma expanding induced hydroacoustic.Third,there is a weak relation between the frequency of laser induced hydroacoustic and laser pulse energy.