Abstract: Due to the harsh environment of agricultural production, vibrations and in-vehicle noise during the use of tractors have a negative impact on the comfort and efficiency of the driver. Damping materials can reduce the amplitude and transmission of vibration by converting it into other forms of energy, and can also reduce structural weight without reducing the strength and stability of the mechanical structure. In this paper, a new liquid apply sound deadener（LASD） is proposed for the lightweight design of tractor bodies, and the balance between vibration damping performance and structural strength is explored. The lightweight design was carried out based on the static stiffness, dynamic stiffness and side impact safety performance of the tractor body. The results showed that the use of damped damping materials can significantly reduce the weight of the tractor body by 4.2%, significantly reduce the vibration amplitude of the tractor body and improve the comfort and efficiency of the driver. The results of the study provide an effective way to improve the performance of agricultural machinery and driver comfort and have practical application prospects.