Abstract: Based on the analysis of existing algorithms, an improved skew detection algorithm for document is proposed.Firstly, enhancement, denoising and binarization of an image are performed.And then, the extraction of the border line and computation of each borderline's angle are done.Finally, the skew angle is obtained by computing the weighted average.By applying LMS algorithm, the proposed algorithm has better accuracy, stability, and adaptation.The experimental results show that the improved algorithm has better performance.