Abstract: In order to reduce the size of the longitudinal transducer and increase the emission bandwidth, a relaxor ferroelectric single crystal/piezoelectric ceramic hybrid excitation transducer was studied. The transducer is polarized in the direction of 011 PIN-PMN-PT single crystal and PZT-4 piezoelectric ceramic hybrid excite, using the principle of multi-mode vibration coupling, through single crystal 32-mode vibration, can flexibly adjust the drive capacity and stiffness distribution between the two vibrators. First, the equivalent circuit of the transducer was obtained by the four-terminal network method and its resonance frequency was calculated. Then, the transducer was simulated and optimized by the finite element method. Finally, a test prototype was made and tested and analyzed. The transducer prototype has an outer diameter of 86 mm, a length of 80 mm, a working frequency band of 13~38 kHz, a maximum transmission voltage response of 144.9 dB, and an in-band transmission voltage response fluctuation of less than 6 dB. It has good broadband and small-size working performance.