In order to ensure that the auxiliary converter of an overseas metro vehicle can meet the noise performance requirements, the statistical energy analysis model of the auxiliary converter is established, and the energy distribution characteristics and noise transmission path of the plate subsystem and the acoustic cavity subsystem are analyzed. The problem of excessive vibration and noise of 1 800 Hz is analyzed for guidance. The results show that the higher noise of test point 2 and test point 5 is related to air transmission, noise transmission and structure radiation noise, and the lower noise of test point 1 is related to the arrangement of sound absorbing materials at the air inlet side. The noise of low-speed half load and high-speed full load conditions is mainly electromagnetic noise of 1 800 Hz, which is twice the switching frequency of IGBT. The vibration spectrum of transformer top panel and air outlet side panel is mainly 1 800 Hz. The vibration and noise can be reduced by pasting damping material and sound-absorbing material at this position. Noise simulation and test can provide guidance for the design and development of metro vehicle auxiliary converter products.