Abstract: Taking a metro vehicle as an example，the problem of large interior noise is tested in the site. The characteristics of abnormal interior noise， the law of sound and vibration transmission in bogie area are detected. At the same time，the interior noise characteristics before and after the wheelupsetting and rail polishing are compared，the influence of wheel-rail roughness on interior noise is analyzed. The results show that the main source of abnormal interior noise is the 30~50mm corrugation of rail surface，and the increasing of rail roughness will significantly increase the radiation of wheelrail noise，and further affect interior noise.