A novel fixture system with advantages of high selfconfiguration and flexibility is proposed to meet the requirements of automotive industry to high modularity and good dexterity of manufacturing systems and all components including fixtures. All clamping elements attached to the endeffectors of parallel mechanisms have high stiffness,high accuracy,reconfigurability and programmability to move in their workspace. While the parallel mechanism,as a support unit of selfconfigurable fixture,has the limitations of workspace and dynamic property. In order to enhance comprehensive working performances,the global kinematics condition index and global dynamic condition index acted as an evaluation criteria of kinematics dexterity and dynamic dexterity were proposed respectively.Furthermore,the fixture mechanism was optimized by means of taking the volume of the workspace,the global kinematics condition index and the global dynamic condition index as objective functions.Finally,the optimized architecture parameters were obtained.