In order to optimize the design of tractor cab seat, reduce the workload of the driver, improve work efficiency, and solve the problem of insufficient technical basic research on the comfort of cab seat of Chinese tractors, evaluation method for seat comfort of tractor cab based on bone joint recognition was proposed. Firstly, based on the analysis of factors affecting the comfort of tractor seat, the human sitting joint angle was selected as the research factor. The consumergrade depth camera Kinect v2 was used to conduct eight driving motion capture experiments on two tractors equipped with different seats. The joint angle information with an accuracy of 0.01° under different driving actions was obtained; then, the joint angle data was imported into the human body modeling simulation analysis software Jack to obtain the human body model, and the joint torque simulation and lower back force were carried out according to different driving actions simulation and analysis to obtain the results of human comfort; finally, based on the analytic hierarchy process, a hierarchical model of the tractor seat comfort evaluation index was constructed, the weight of each index was determined and the consistency test was performed, and the original data of all the indicators involved were processed and calculated to obtain the comprehensive evaluation result of seat comfort. The simulation results showed that compared with tractors with ordinary seats, when working on tractors equipped with ergonomic seats, the ability of digital humans to complete actions was increased by 10 percentage points, and there was no joint discomfort. The pressure can be effectively reduced by 80N in the driving posture and 370N in the twisting posture, and the lateral shear on the waist was also reduced, proving that the digital human was more comfortable on this tractor seat. By analyzing the seat comfort evaluation matrix, it can be obtained that the seat comfort designed according to ergonomics was better than ordinary seats. The evaluation results based on the bone joint recognition method were consistent with the results analyzed based on the analytic hierarchy process, which proved the feasibility and effectiveness of the tractor cab seat comfort evaluation method based on bone joint recognition. This evaluation method can provide certain reference basis and guiding countermeasures for the ergonomics research of tractor cab seat and the accurate and efficient optimization of tractor seat design. 