By combining the finite element analysis with the kinematical theory，a modeling strategy of the global
parametric finite element model and an optimal design of structural parameters are proposed for a 4-DOF high-speed parallel manipulator which can realize SCARA (Selective Compliance Assembly Robot Arm) motion． First，based on the inverse kinematic analysis of the Cross-IV manipulator，the finite element model of the manipulator under different conditions of configurations，dimensions and structures can be rapidly constructed by means of the Ansys programming language APDL． Next，by using the parametric finite element model，a circular modeling strategy is presented to evaluate both the global static stiffness and the low-order natural frequency distribution of the whole machine，and the configuration of the worst performance is obtained． Finally，a novel performance index is defined to estimate the dynamic characteristics of the manipulator，and the effect of structural parameters on the dynamic performance of the system is deeply analyzed through the orthogonal experiments of a set of scale parameters．Thus，a set of optimal structural parameters are obtained．