The underwater energy radiation characteristics of the airgun seismic source is studied based on the underwater wavelet data collected in the airgun excitation experiments in Binchuan,Yunnan. The empirical formula for calculating the bubble pulsation period and the maximum radius of the underwater airgun seismic source is obtained. The results show that:① The energy radiation efficiency is higher vertically than horizontally. ② The vertical bubble energy radiation efficiency increases with the increase of the gas supply pressure. ③ The vertical energy radiation efficiency of the airgun seismic source is 9.4%when the gas supply pressure is 15MPa. ④ The higher of the gas supply pressure,the farther of the constant distance for the overlay enhanced of the pressure wave of the airgun seismic source.