Abstract: Motion precision and driving stroke are key indices for performance evaluation of the micro-motion mechanism. The design theory pursuing for precise displacement amplification ratio is of great importance. Taking a micro-driving displacement amplifier module as example, a parameter design method was presented targeting for precise displacement amplification ratio. According to the pseudo-rigid-body model of this micro-driving displacement amplifier module, motion equations were built based on the elastic deformation relationship of the flexible components. A corresponding relationship between system energy and flexible unit displacement was deduced taking advantage of Lagrange equation and principle of conservation of energy. A strategy for average distribution principles of system energy was put forward to make structure parameters correlative. This procedure could realize the progressive parameter design for micro-driving displacement amplifier module. For this example, the ANSYS software was also used to verify the theory. Results show that, the deviation between theoretical calculation and FEA simulation is below 6.25%. It provides an important basis for parameter design of the micro-driving mechanism targeting for precise displacement amplification ratio.