Abstract: Watermark embedding algorithm based on quantizing frequency domain parameters of digital audio signal is proposed in this paper. The watermark is embedded by quantizing amplitude or phase of discrete Fourier transform coefficients of digital audio signal. The algorithm proposed in this paper is digital-audio-signal-independent, that is, the original audio signal is not required in the procedure of extracting watermark. The experimental results show that the algorithm is robust to many operations on digital audio signal, such as filter, lossy compression, and so on.