"Fragmentation composition" is a design composition theory proposed by Jiang Jin. It is originally a method of composition and composition of design. However, years of design creation practices have found that "fragmentation composition" theory is also a very good method when applied to design modeling. The theory of "fragmented composition" enriches the design means and methods of design modeling, and becomes an important tool for modern designers to innovate visual elements, optimize visual information and transform visual elements from concrete to abstract. Starting from the concept analysis of "fragmentation composition", this paper discusses the principle of "fragmentation composition" in the practical application of book binding design, the application value and characteristics reflected in the design, and makes an objective analysis of some excellent "fragmentation composition" application works, in order to provide some useful references for the application of "fragmentation composition" in modern book binding design.