In this paper, aiming at the problems of low reliability and high failure rate of crawler combine gearbox, based on the theoretical design, the dynamic simulation of transmission system is carried out by using ADAMS software. The simulation results show that the transmission system is similar to the theoretical design results, and the fluctuation of the angular velocity curve of each axis is small, which preliminarily verified the transmission stability and accuracy of the gearbox. Then, transient dynamics analysis and modal analysis of critical components were performed by ANSYS simulation software. The results show that the strength of the critical parts meets the requirements and the critical parts do not resonate. Finally, the gearbox was prototyped and assembled on the test vehicle. The results show that the gearbox has good straight-line driving and cornering performance. The minimum natural frequency of the axis is 182.49HZ, which is lower than the frequency of its operation and does not cause resonance. The results of this paper will provide a basis for designing a gearbox design and dynamic load analysis of rice tracked combine harvester device.