Abstract: Semi-fragile watermarking methods aim at detecting unacceptable malicious manipulations, while allowing for acceptable regular manipulations such as lossy compression. In this paper, a semi-fragile audio watermarking algorithm for copyright protection and content authentication is proposed. The features of the proposed algorithm are as follows: 1) The original audio signal can be adaptively divided, and the watermark depth can be intelligently adjusted according to human auditory masking and local audio character; 2) The copyright protection and content authentication for digital audio can be utilized simultaneously. Experimental results show that our semi-fragile audio watermarking scheme is not only inaudible and robust against various common images processing, but also fragile to malicious modification. Especially, it can detect effectively the tampered regions.