In this paper, a new type of the positioner is proposed, which has with dual-drive and dual-screw. Comparing with the positioner of the traditional gear transmission system, the positioner with the new mechanism has less power and less work space. Based on the designing requirements, we optimized the dimensions of the mechanism of the positioner, and carried out the kinematic and dynamic analysis of the positioner. The strength and the rigidity of the positioner are analyzed by the use of FEM. Finally, according to fuzzy mathematical theory, the reliability of the mechanism motion of the positioner is studied.