Abstract: In the late summer of 1996, a combined acoustics and physical oceanography experiment was performed in the midst of the Yellow Sea. Here the oceanographic data are analyzed and the internal wave spectrum is constructed. It shows that the internal waves are dominated by the first modes and the spectral density is approximately proportional to ω^-3/2. Based on the internal wave spectrum, a model of the induced sound-speed distribution is developed, and computer simulation is conducted for CW signal propagation by using the PE method. Numerical results of the sound intensity fluctuations are presented for comparison with the experimental data.