Based on analysis of micro driving, one piezoelectric micro driving mechanism is designed. Flexure hinge is used to implement non-mechanism friction as well as high sensitivity of micro driving. In accordance with the principle of leverage amplification, the flexure hinge amplifies the output displacement of stacking piezoelectric ceramic and it meets the need of working for phase shifter in laser testing system. The theretical analysis for flexure hinge is presented as well as its math modeling. Finite element analysis is used to optimize the main parameters of mechanism.