Abstract: In this paper,characteristics of multilayer ferroelectric single crystal structures with non-uniform layer thicknesses were studied and optimized for broadband ultrasonic transducer design.The theoretical model of multilayer piezoelectric structures based on complex piezoelectric material parameters has been established.Simulated Annealing optimization was used to optimize the layer thicknesses of a multilayer PMN-PT structure.The effects of layer thickness variations on the multilayer device were analyzed.It is verified that multilayer ferroelectric single crystal structures with non-uniform layer thicknesses are able to be used to design and manufacture high performance broadband ultrasonic transducers with theoretical simulation and practical measurement.