Based on the mountain crawler tractor (referred to as mountain tractor ) developed by our team, a collaborative control system for vehicle body and farm tool attitude was designed. In view of the different attitude adjustment requirements of body leveling and farm tools profiling during the contour operation of mountain tractors, the control strategy of the whole system was constructed on the basis of establishing the kinematics model of body and farm tools, and the collaborative control system was designed. Among them, PID algorithm and double closed-loop fuzzy PID algorithm were used for the control of body and farm tools, respectively. The control algorithm was simulated and analyzed based on Simulink. The results showed that the PID algorithm can meet the basic leveling requirements. The control effect of using double closed-loop fuzzy PID algorithm to realize the attitude adjustment of farm tools was better than that of PID algorithm. Finally, the static and dynamic tests of the coordinated adjustment of the unit attitude were carried out. The results showed that when the static adjustment was carried out on the slope of ±15°, the maximum error of the body roll angle was 1.10°, and the maximum error of the farm tool roll angle was 0.46°. In the dynamic operation on the slope of 14°~16°, the maximum error of the roll angle of the body was 1.90°, and the maximum error of the roll angle of agricultural machinery was 0.93°. It can be seen that the accuracy and stability of the attitude cooperative control system can meet the requirements of slope contour operation in hilly and mountainous areas.