The invention discloses a posture adjustment adaptive control system of a mountain caterpillar tractor. The posture adjustment adaptive control system is composed of a posture sensor, a signal conditioner, a posture adjustment controller and a posture adjustment actuator. The posture adjustment actuator is a posture adjustment mechanism of the mountain caterpillar tractor and composed of an electromagnetic reversing valve and a hydraulic cylinder. According to the posture adjustment adaptive control system of the mountain caterpillar tractor, posture angle information of the mountain caterpillar tractor on a sloping field can be automatically converted into movement information of the posture adjustment actuator through the posture sensor, the signal conditioner and the posture adjustmentcontroller, and the mountain caterpillar tractor is controlled to do movement so as to further adjust the posture angle of the tractor, so that a tractor body of the tractor can automatically adapt tothe change of the ramp angle and always maintains horizontal. The posture adjustment adaptive control system can be used for posture adjustment adaptive control of the mountain caterpillar tractor when driving or working under a sloping field working condition, practicability is high, and the high application and popularization value is achieved.