Aiming at the current attitude-adjustable hilly tractors can only achieve static leveling, height difference leveling, and low leveling accuracy, an attitude adjustment device of the twisting and swinging wheel hilly tractor was designed. This device realized the tractors adaptation to complex roads by adjusting the relative rotation of the front and rear vehicle bodies. Firstly, according to the requirements of the special pavement in hilly areas, the stability of tractors on slopes was studied, and a twisting and swinging attitude adjustment device was designed. Then, dynamic simulation of twisting and swinging attitude adjustment device was carried out, model of the tractor was established, and dynamic simulation analysis of multiple working conditions was performed. The dynamic simulation showed that the device maximum rotation angle was 15.2°, the maximum inclination angle for the tractor to maintain stability on longitudinal slopes was 23.2°, and the maximum inclination angle for stable driving on transverse slopes was 16.8°. Finally, field trials of prototypes were conducted. The test results showed that the average angle of rotation of the twisting and swinging attitude adjustment device was 15.03°, the maximum longitudinal climbing angle of the tractor was 25.6°, and the maximum transverse climbing angle was 16.2°. The average productivity of rotary farming was 0.65hm2/h, and the average productivity of plow farming was 0.36hm2/h on the ground with a slope of 15°. The tractor met the design and technical requirements, and can better adapt to the hilly and mountainous environment, and it can meet the normal operation requirements of the hilly and mountainous areas.