Aiming at the problems of deep muddy feet and poor driving performance of working machinery in southern paddy fields, the subsidence characteristics of paddy field dynamic chassis wheels were studied through traction performance test with an example of high clearance chassis, whose ground clearance is 1 100-1 500 mm. Under the heavy load of 800-1 100 kg, the wheel load and slip rate were taken as test variables, and the wheel subsidence coefficient, driving coefficient and hook traction coefficient were taken as test indexes. The subsidence model of high ground clearance chassis is established. The results show that the hook traction coefficient of the wheel is directly proportional to the driving coefficient and inversely proportional to the subsidence coefficient, respectively. The field test was used to obtain the correction parameter of the model, which was positively correlated with the load and in the range of –0.3 to –0.19. It is lead to the error between the fitted value and the measured value in the field test is less than 5%.