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Hillside crawler tractor (equipped with attitude adjustment mechanism) has good stability and obstacle-surmounting performance, and it is especially suitable for operation on hilly and mountainous slopes. However, due to the existence of the slope angle, the stress distribution under the tracks on both sides of the tractor is extremely uneven, which reduces the adhesion and passability of the tractor. Aiming at the problem that the internal stress distribution law of sloping soil is not clear when the hillside crawler tractor is driving and operating on the contour line slope, on the basis of in-depth analysis of the basic laws of the maximum grounding specific pressure and stress transfer of the crawler under sloping conditions, the EDEM-RecurDyn coupling method was used to carry out the simulation test, and the method of burying the soil pressure sensor was used to carry out the static test based on the small slope soil trench and the dynamic test on the slope field respectively. The static test explored the vertical stress distribution law of soil at different depths under the influence of moisture content, initial compactness, loading quality and slope angle. The variation law of the vertical, horizontal and lateral stresses of soil under the crawler with operating speed, state of the tractor body (leveled and unleveled) and the load when the tractor drive and rotary tillage on the contour line slope was studied by dynamic tests. And the influence of crawler tension on soil vertical and horizontal stress distribution was analyzed. The results showed that the vertical stress under the crawler presented a stress peak at the axis of each roller. The horizontal stress had a stress peak at the front and rear of each roller axis. Appropriately increasing the operating speed can reduce the peak value of vertical and horizontal stress in the soil. When the tractor speed was increased from 0.5km/h to 1.5km/h, the peak value of vertical stress was reduced by 35%, and the peak value of horizontal stress was reduced by 27%. The leveling of the tractor body can better improve the uniformity of vertical and horizontal stress distribution under the crawler on both sides. The vertical stress peaks on the low and high sides of the slope were respectively decreased by 13% and increased by 18%, and the horizontal stress peaks on the low and high sides of the slope were respectively decreased by 28% and increased by 23%. When the crawler tension was reduced from 1.2×104kPa to 8.0×103kPa, the vertical and horizontal stress peaks were respectively decreased by 31% and 22%, which showed that moderately reducing crawler tension reduced soil compaction. The research result can provide a theoretical basis for the optimization of relevant parameters of hillside crawler tractors, so as to improve the uniformity of soil stress distribution on slopes and alleviate the soil compaction.