Equipped with sonars, autonomous underwater vehicles (AUVs) are essential tools for underwater acoustic surveillance. Vibration and radiated noise significantly impact acoustic sensing performance, making their reduction crucial for AUVs used in such missions. The power source in the AUV’s propulsion system is the primary source of vibration and noise. This paper presents an approach to optimizing the power source to reduce vibration. To evaluate the performance improvement of the optimized power source compared to its performance before optimization, experimental evaluations were performed. Vibration experiments on the power source conducted in air validated the effectiveness of the optimization. Additionally, radiated noise experiments on the propulsion system were conducted in an anechoic water tank to evaluate the impact of different design parameters on radiated noise levels. Comparative analysis of the experimental data revealed that, within the frequency range of 20–1500 Hz, the total sound pressure level was reduced by 5.9dB. In the frequency range of 1500–9000 Hz, the total sound pressure level was reduced by 27.2dB. These results verify the effectiveness of the optimization in reducing vibration and noise in the AUV propulsion system.