To improve the actuator stroke of laminated piezoelectric ceramic and to let it be with the ability of reciprocating symmetrical actuation,a diamond piezoelectric micro displacement amplification mechanism was proposed based on the triangle amplification principle.The laminated piezoelectric ceramic was taken as a driving element of the mechanism.On the basis of the triangle displacement amplification principle,a two-way active output on both sides of the equilibrium position was achieved while amplifying the output displacement of the laminated piezoelectric ceramics.A corresponding driving method was proposed to achieve the control of direction and magnitude of the output.The working principle of the mechanism was analyzed,and the geometric calculation results show that the magnification is 2.9,which is close to the simulation calculation magnification result 25 based on finite element model.A test prototype was developed to test the performance of the mechanism.The experimental results indicate that the maximum output displacement of the mechanism is 32 microns(±16 microns) when the driving voltage is 200 V and its amplification is 2.4 for the displacement of the laminated piezoelectric ceramic,which is close to the theoretical calculation.The experiment also shows that the signal frequency has a minor effect on the displacement output.The mechanism achieves both of the displacement amplifications and two-way movement outputs as desired.