The work aims to a portable digital watermark detection method based on ARM system and singular value decomposition according to discrete wavelet transform and matrix, so as to meet the requirements of high anti-print photo-scanning and low algorithm complexity in portable digital watermark detection. In ARM-based portable system, image acquisition module was used to read watermark image information, DWT-SVD digital watermark algorithm was applied to detect watermark, and detection results were displayed on LCD. The portable device based on ARM processor could accurately detect watermark information, and extract the NC value of watermark of 0.7. The method has good anti-printing and photo-taking performance and low computational complexity, and can be applied to portable digital watermarking detection equipment.