The invention discloses a digital watermark embedding and extraction method based on chaos sequences. The digital watermark of the chaos sequences is used for carrying out scrambling, and the pertinence of the original watermark and the scrambled digital watermark is removed through the scrambling, so the digital watermark has the features like flat noise. Thereby, the transparency of the digital watermark is improved. The position of the watermark embedding into a DCT block is determined through the chaos sequences, the safety of the algorithm is improved, and better robustness on the large-area cutting attack can also be realized. In the watermark embedding process, firstly, image sub blocks carry out discrete cosine transform (DCT), and the energy can be converted into low-frequency factor compression blocks; and after the conversation, the obtained low-frequency component matrix A carries out singular value decomposition (SVD), and at the same time, the position of the watermark embedding into the DCT low-frequency compression blocks can be determined and the embedding intensity can be regulated through the chaos sequences. Thereby, the calculation complicity can be reduced, in addition, the embedding quantity is also increased, the robustness of the watermark is improved, and the capability is improved for resisting ordinary attack, so the invention has wider practicability.