The invention discloses a dynamic property optimization design method for foundation major parts of a machine tool. The method includes the steps that a machine tool assembly is simplified according to the dynamics simulation analysis requirement, and the simplified assembly is imported into ANSYS/Workbench for mesh generation, material setting and boundary condition setting to complete modal analysis of the machine tool assembly; in harmonic response analysis, the maximum amplitude response values of the end of a spindle box of the machine tool assembly under the action of simple harmonic force in the X direction, the Y direction and the Z direction are obtained by simulating the actual working state of a tool; finally, experiment design of quality characteristic parameters of the foundation major parts is carried out with the parametric analysis technology, and a response surface model between the dynamic property response values of the machine tool and the quality characteristics of the foundation major parts is obtained through fitting. By analyzing the response surface model, the weak link of the foundation major parts in the dynamic property of the machine tool can be qualitatively found out, the tendency of influences of changes of the foundation major parts on the dynamic property of the machine tool can be quantitatively predicted, and the precision of machine tool design can be improved.