The generalized module is one of the basic elements of parametric product platform, which can effectively support product variant design and mass customization design. A similarity analysis method for the non-isomorphism generalized module is proposed to support the precise configuration of product’s function, structure, and process. The structure, function, and process information of product modules are extracted from the product lifecycle management/product data management database and converted into eigenvector by range identification. Then, the parameters of different scales in non-isomorphism classes are normalized to eliminate the effect of different dimensions. The similarity measure of function and process information is completed by vector matching. The function equivalence classes and process equivalence classes are obtained using the proposed classification algorithms. The results of similarity analysis can increase the flexibility of product variant, meet the needs of customization, and thus directly support the precise configuration. Finally, the feasibility and effectiveness of the proposed method are verified by a case study of high and middle pressure valves.