Aiming at the clustering module existing in the product component assembly process, the granularity of the clustering module is too large, and the interference and conflict between components. A method for modeling and optimizing the assembly process of complex product components is proposed. The analysis network model was coupled with the Fuzzy Design Structure Matrix to quantify the information dependence between components. And then the transitive closure method was used to obtain the fuzzy equivalence matrix with reflexivity and symmetry. Clustering of complex components based on cut-off thresholds and utility theory. Finally, the input and output sets of each component module were determined, thereby optimizing the execution order of the assembly. At the same time, improve the core competitiveness of products. Taking the assembly of the leg components of the hydraulic four-legged robot as an example, the validity and feasibility of the method are verified. New design ideas are provided for component assembly process planning.