The present invention belongs to image signal processing field, in particular a significative digital watermarking algorithm of the supercomplex frequency domain. The algorithm processing quick supercomplex Fourier transform to the color carrier image, selecting proper frequency band to embed in the watermark data in the supercomplex frequency domain, and repairing the value of coefficient of asymmetry, resolving the problem of the precondition of the supercomplex frequency domain embedding in the watermark, ensuring process transmittion by the red, green, blue of the color image when embedding in the watermark image, paving a road for further study of the color image watermarking algorithm of the supercomplex frequency domain. The algorithm also provides a regulation of ''intersecting redundancy embed'' of the watermark data, further improving the Robust of the digital watermark. The analyzing result shows that the proposed method diffuses the error caused by watermark to the whole imge by supercomplex Fourier transform, and diffuses to each weight of red, green, blue colors, achieving excellent combination of the non intangibity and safety of the digital watermark.