The invention relates to an expansion and shrinkage prediction model of a printed circuit board, which comprises the following steps of: according to the production model of the printed circuit board,obtaining materials selected by the printed circuit board, a laminated structure and residual copper rate information of each layer; according to the lamination process of the printed circuit board,dividing the lamination process of the printed circuit board into seven stages, establishing an expansion and shrinkage prediction model epsilon i of each core board layer of the printed circuit boardaccording to the size change rate of each layer of each stage, and establishing an expansion and shrinkage prediction model epsilon PCB of the printed circuit board according to the size change rateof each layer of each stage. The expansion and shrinkage prediction model of a printed circuit board can be used for accurately predicting the expansion and shrinkage of the laminated printed circuitboard before production, so that the expansion and shrinkage pre-release coefficient of each layer can be conveniently, quickly and accurately given, the qualification rate of PCB finished products can be improved, the influence of expansion and shrinkage tests on the product processing period can be reduced, and the processing cost of the products can be reduced.