The work aims to put forward a full frequency-domain color image double-watermarking algorithm based on NSCT and discrete wavelet transform, so as to improve the ability of color image to resist geometric attacks. Firstly, the blocks of watermark image were scrambled based on Fibonacci transform and the intensity factor embedded was adaptively selected. Then, y component of the color carrier image was firstly blocked and then subject to NSCT decomposition and DWT transform. The embedded array generated was randomly selected. The watermark was circularly embedded into the carrier image by regulating the singular value of each block of embedded array. The maximum singular value of each block was extracted from the watermarked image and 2D quantized to generate no watermarks. The simulation showed that, the proposed algorithm had good invisibility and effective robustness against such common geometric attacks as shearing, filtering, scaling and Gaussian noise. The algorithm has solved the problem of interference between single watermark function and single double-watermarking algorithm, and it can protect the copyright and verify the contents of digital products at the same time. Such algorithm has good robustness and invisibility.