Abstract: A kind of moving reflector's mechanism with small coupling displacement was studied to control the reflector's movement of Michelson interferometer in FTIR spectrometer. On the basis of a single and double parallel four-bars mechanisms, the moving reflector's mechanism was created by employing flexure hinges. And the static and dynamic characteristics of the mechanism system driven by piezoelectric ceramic(PZT) actuator were analyzed. The results reveal that there is no coupling displacement produced with the mechanism when force is symmetrical, while the coupling angle of the mechanism is small to 10-6(in degrees) when force is unsymmetrical, and that the maximum stress of the mechanism is about 0.5 times lower than that of double parallel four-bars mechanism at the same output displacement. Moreover, the natural frequency fn of the electromechanical system composed of PZT actuator and the mechanism is 4 times higher than the fundamental frequency f of the mechanism, which meets the requirement of dynamic performance. The study will provide a basis and some valuable theoretical guidance for future research.