In order to solve the problem of increased electric impedance matching difficulty of piezoelectric elements in largescale ultrasonic arrays, a multilayer piezoelectric element construction method based on transverse vibration mode is proposed. Based on the characteristics of piezoelectric ceramics with multiple vibration modes, the piezoelectric elements working in thickness vibration mode are converted into transverse vibration mode. In this process, the vibration direction of piezoelectric components is unchanged, the area of electrode increases and the distance between electrodes decreases, so that the fixed capacitance increases and the electrical impedance decrease. In this paper, a twolayer structure mode conversion method for the piezoelectric element is proposed. Combined with the simulation analysis, the piezoelectric elements based on transverse vibration mode are designed. Without impedance matching, the electric impedance is reduced to nearly 50 Ω.