A piezoelectric displacement amplification mechanism, driven by stacked piezoelectric ceramics and based on the triangular amplification principle, is designed. Finite element analysis is employed to simulate the static and dynamic performance of the mechanism. To optimize its performance, the displacement amplification ratio and structural stiffness are maximized as objectives, considering the influence of dimensional parameters on performance. The optimal Latin hypercube sampling method is used to generate sample points in the design space, followed by finite element computation. Based on the computational results, a surrogate model of the optimization objectives is constructed using the Kriging method, and the non-dominated sorting genetic algorithm （NSGA） is applied to obtain the optimal solution set. Simulation results demonstrate that the displacement amplification ratio improved by 17.4%and stiffness increased by 5.3% compared to the initial design. An experimental prototype is fabricated based on the optimized dimensions, and test results show that the displacement amplification ratio of the designed amplification mechanism is 8.49, which closely matches the ratio obtained from the simulation.