In the analysis of simple wire-driven platform (SWDP) mechanisms, the tension and the posture of each wire can be formulated, and expressed in an integrated screw representation naturally. In this study, a unified approach for analyzing the kinematics and kinetics of SWDP mechanisms based on the screw theory is proposed and developed, which includes the screw-based Jacobian, the static and dynamic equilibrium of wires and platform, and the singularity analysis. Via using the unified screw-based approach, the investigation on the characteristics of SWDP mechanisms, therefore, can be more efficient and simplified. An example is presented to demonstrate this unified approach.