The characteristics of the Electric Vehicle (EV) traction motor system are different from the traditional industrial motor system, and the noise spectrum characteristics are also distinguished. Based on the theory of sound intensity, the experiments of noise characteristics of the Electric Vehicle traction motor system are research through the measurement at discrete points firstly. The figure of noise spectrum characteristics are analyzed in details, and the figure of 1/3 octave to sound intensity and sound pressure as well as the noise spectrum characteristics ca be acquired. In addition, according to the experiments, the noise spectrum characteristics of each part of the Electric Vehicle motor system have been established.