In order to analyze impacts of secondary sound source distribution on vehicle interior noise, the finite element model of a vehicle is built. The optimal distribution of secondary sound source is obtained from an input-output relationship between source locations and sound pressure level, noise characteristics and noise reduction. The results show that the noise reduction effect is the best when the secondary sound source is placed on the side wall of the driver and crew, and the noise reduction effect is more than 7.4dB. When the secondary sound source cloth is placed above the head of the driver and crew, the noise reduction effect is the second. When the secondary sound source is placed at the bottom of the chassis, the noise reduction effect is the worst. When the secondary sound source is placed near the head of the main driver’s seat, the noise reduction effect of the local space near the head of the main driver’s seat can reach more than 10 dB. It is shown that placing secondary sound sources in the vehicle interior can effectively reduce the vehicle interior noise and improve the sound quality of the whole vehicle.