Studying painting, drawing, sculpting, and graphic design are all included in an art and design degree. Basic design ideas, colour theory, critical analysis, and creative approaches are taught to students majoring in art and design. One of the key elements that determine the calibre of art and design is colour matching. Modern art design makes extensive use of computer technology. To create high-quality art pieces, designers must thoroughly research computer colour matching. This paper is based on a knowledge of the colour matching of the art design. This paper uses computer technology to successfully select the hue and colour quantity rate of a mathematical framework. At the same time, it should select the style of colour matching style, background hue, and colour quantity. It is proposed to employ cyan, magenta, yellow, key (CMYK), hue-saturation-brightness (HSB), red, green, and blue (RGB), and other modes to get the approximate hue sum, which can serve as a useful benchmark for the modernization of art design. The experimental results demonstrate that the two groups of colour matching selected for this paper have high colour difference accuracy, but the formula accuracy provided by the weight factor for colour difference is superior to that provided by other weight factors whether it is the formula accuracy provided by computer colour matching or the accuracy of actual art images.