Abstract: A fragile blind watermarking algorithm of high detection rate for color image integrity authentication was proposed.Firstly, we divided the R、G、B components of image into some blocks, operated integer wavelet transform for each block once, and changed wavelet coefficients through function mapping into the initial value of chaos.The watermark information was obtained by iterating of chaos and quantifying the chaos sequence.At last, we embedded the watermark information into wavelet transform domain randomly.The algorithm improved safety of watermark information and sensitivity of fragile watermarking.