Abstract: In order to improve the performance of Stewart platform decentralized control system in joint workspace,a control strategy based on linear parameter varying(LPV)method is proposed.Firstly,the dynamic model in joint workspace is formulated for the manipulator.Based on the analysis of manipulator inertia matrix,it is pointed out that each subsystem equivalent load variation and the coupling interference between the subsystems are the main problems for decentralized control.Secondly,the inertia matrix is decomposed into the sum of a diagonal matrix and a coupled matrix.Coupling between the subsystems is regarded as disturbance to each strut,and the dynamic model is obtained for each subsystem. Finally,according to the characteristics that the subsystem equivalent load changes greatly with the moving of the upper platform,the linear parameter varying(LPV)control method is introduced.Consequently,the.controller parameters can suit the subsystem load variation,and the conservativeness is decreased.Simulation results are given to verify the validity of the proposed approach.