In order to understand the influence of different parts on the aerodynamic noise of the claw alternator for vehicle at high speeds, this research studies the aerodynamic noise characteristics of the claw alternator. The no-load acoustic power level experiment of the claw alternator for vehicle is carried out to verify the accuracy of the numerical simulation. The noise sources of each order are determined by using with or without front and rear fan blades, claw and cylinder envelope instead of claw pole. The contribution of front and rear fan blades and claw to different orders of noise are Clarified. The results show that dipole is the main noise source at high speed. The front blade mainly affects the aerodynamic noise in 8th, 10th, 12th and 16th order. When the front fan is removed, the aerodynamic noise in 12th and 16th order is reduced by 6.54dBA and 9.04dBA, respectively. The rear fan mainly affects the aerodynamic noise in 6th, 8th and 10th order. When the rear fan is removed, the aerodynamic noise in 6th, 8th and 10th order is reduced by 11.75dBA, 2.42dBA and 7.38dBA, respectively. The influence on the aerodynamic noise is small with or without claw, but the flow field is affected when the cylinder envelope is used to replace the claw pole, and the 8th order noise has a certain change. It also shows that the front and rear fans are main sources of the aerodynamic noise.