Abstract: Digital watermarking is a technique, which protects digital product copyright and does not appear until two years ago. And its goal is to protect legal copy and distribution of digital product, it has been the hotspot of international academia. Digital watermarking includes algorithm design and attack technique, which are contrarily promoting each other. In this paper the concept and applications of digital watermarking are briefly discussed, the current various attack methods are fully analyzed and summarized. Several directions of development of digital watermarking at next stage are proposed. These are of great importance to improve and design watermarking algorithm.