In this study, coupled mode piezoelectric devices for AE sensor application with excellent displacement and piezoelectric characteristics were simulated using ATILA FEM program, and then fabricated. Displacements and electromechanical coupling factors of the piezoelectric devices were investigated. The simulation results showed that excellent displacement and electromechanical coupling factor were obtained when the ratio of diameter/thickness was 1.0. The piezoelectric device of ф/T= 1.0 exhibited the optimum values of fr= 406 kHz, displacement= 6.11 × 10^-8[m], k_eff= 0.648. The results show that the coupled vibration mode piezoelectric device is a promising candidate for the application of AE sensor piezoelectric device.