The semi-fragile watermarking algorithm based on Hadamard transform and SVD decomposition was proposed to distinguish normal image processing operations from malicious tampering.Firstly,the copyright image Can Sleeve was SVD decomposed,and Hadamard transform was performed on all image subblocks.The watermark was embedded by quantization method.The algorithm was sensitive to tampering and had good Server ability to recognize tampering position,and had strong resistance to JPEG compression.