Abstract: In order to reduce the low frequency noise of the boat tractor cab, the cab wall structure was optimized. Firstly, the acoustic-vibration coupling model of the cab was established, and the modal-based acoustic-vibration coupling method was used to calculate and analyze the acoustic environment inside the cab to obtain the vibration frequency corresponding to the higher peak sound pressure reliability. Then, the plate contribution analysis was performed on the cab, and the plate with a larger noise contribution at the higher sound pressure peak was obtained. Finally, the noise reduction mechanism of the periodic perforated air pressure film damping structure was analyzed, and it was applied to the plate with a large noise contribution. The results showed that by laying periodic perforated air pressure film damping, the cab noise was reduced by 6 dB, 11 dB and 10 dB respectively at the peak sound pressure, and the low frequency noise of the cab was significantly reduced. The research can provide a theory for the noise reduction of the boat tractor cab.