In this paper, the solution region synthesis methodology (abbreviated as SRSM below) for the eight-precision-point path synthesis of planar four-bar mechanisms is presented. The so-called solution region synthesis methodology represents an infinite number of mechanism solutions in a plane, and the solution region is the area where the mechanism solutions are distributed in the plane. The x-coordinate and the y-coordinate of the plane are both taken as the concerned parameters of mechanisms. Furthermore, characteristic curves of mechanisms can be expressed in the plane. In addition, a defect judgment method is proposed, which can be realized in the computer program. The defective solutions can be eliminated efficiently, and the solutions without defects are obtained using the proposed method. After considering and imposing additional design requirements, the linkages of different types and different curve shapes are classified in the solution region. Finally, taking the path generation for eight points as the example, the methodology of establishing the solution region and the feasible solution region are presented, and the synthesis results are illustrated.