Snapping shrimp noise at a site in the coasts of the southern sea and the Yellow Sea of Korea was measured for one day on August, 2001 and 2002, respectively. The waveform of the snapping shrimp noise was a temporal waveform with a positive broad peak pressure at initial time and a negative narrow peak pressure at after the time. The frequency spectrum of the snapping shrimp noise broadly appeared between 0 and 70 kHz. Main frequency response bandwidth was between 2 and 20 kHz. The diurnal variation of snapping shrimp noise spectra was dominant at sunset and sunrise. The snapping shrimp noise observed in the coast of the southern sea of Korea dominantly affected the ambient noise levels between 2 and 20 kHz, while that in the coast of the Yellow Sea of Korea weakly affected the ambient noise levels. Snapping shrimp noise was also measured in anechoic water tank under laboratory conditions. Typical waveform of the snapping shrimp noise was similar to that measured in the coast. The peak-to-peak source levels varied from 181 to 191 dB re 1Pa. The frequency spectrum of the snapping shrimp noise broadly appeared up to about 400 kHz.