We set three microphones, each with a parabolic reflector, to measure vehicle noise on the Yamanashi Maglev Test Line. Using a personal computer, we analyze the noise from the surface of the car. In this paper, we explain the noise measuring system used for this study and data processing, focusing on the calculation of sound-levels, analysis of time-dependent signals and visualization of the noise. We started to measure the noise in April 1999 to collect the data required to reduce the noise level. There is no noise from the car windows as has been expected, since we have designed the window to be smooth and even on the outer surfaces, while high-frequency noise from around the trucks and doors is recognized at 500 km/h. The noise of gas turbine is at low levels.