According to the coupling and nonlinearity of the wire-driven parallel robot(WDPR) system, and taking the 6-DOF WDPR-8 system as the research object, a PD control law is designed based on dynamic equations of the system, and a Lyapunov function is constructed according to the designed control law. The stability of nonlinear parallel control systems is analyzed based on the Lyapunov stability theory and LaSalle theorem. The results show that the system tends to be asymptotically stable. Finally, in the light of the support of the aircraft model for wind tunnel test, the correctness and feasibility of the designed control law is proved by the simulation experiments. The simulation results show that, the control performance of the system is good, which provides the basis for the practical application.