The dispersion analysis of explosive signals and measurements of individual mode attenuation in the Yellow Sea is reported. By adjusting input parameters of a normal mode computer program and making the calculated results coincide with field data, the compressional wave velocity and attenuation in the sediment for the frequency range of 80–800 Hz is simultaneously deduced. The sea‐bottom velocity, attenuation, and its frequency dependence, probed from two sea areas with a different depth and sound velocity profile in the summer and the winter, are very close. Resultant sea‐bottom attenuation approaches the results of earlier workers at the upper end of the frequency band and joins with the data obtained by others at the lower end, and the absorption appears to have a nonlinear frequency dependence (α=0.37f1.84dB/m kHz). The errors due to the change of environmental parameters (such as water depth, water sound velocity profile, sediment density, and seafloor roughness) are discussed.