Using COMSOL software, a simplified analysis model was established, and the finite element analysis of the support column capacitive micromachined ultrasonic transducer(CMUT) model was carried out, and it was compared with the circular cavity CMUT model. The results show that the resonance frequency of the support column CMUT model is 10 kHz and the collapse voltage is 52 V, which is suitable for the low-frequency design. Comparing the support column CMUT model with the circular cavity CMUT model, it can be seen that the former model has a larger active area, less parasitic capacitance; higher device sensitivity, lower collapse voltage, and larger amplitude of membrane, but the sound signals emitted during working will be weaker than the latter.