In the most existing methods of digital watermarking, authors modify more or less the original image data for embedding watermarks，which limits the robustness and security. The transparency of watermarks can be improved by zerowatermarking since it need not modify the original image information. In this paper, a zerowatermarking algorithm based on integer wavelet and LPM is proposed. We get the secret image through the scrambled watermarks and low frequency sub images after LPM and lifting wavelet transformation. The watermarked image can be extracted from the secret image. This algorithm improves the transparency and security.