Abstract: An indoor slope model is designed and constructed for experimental test. A sliding surface is pre-installed in the slope model. The slope is reinforced with pile and sheet pile wall respectively. The geometry dimensional similarity ratio of the indoor slope model to the actual slope size is 1:25. The model is horizontally loaded step by step. Comparative analysis on the force and deformation characteristics of the two different supporting structures under horizontal load is conducted. The results show that the failure process of the slope-support structure system is divided into three stages. They are the sliding soil compaction stage, the main deformation stage of supporting structure, and the failure stage of supporting structure stage respectively. Transfer efficiency of soil pressure behind the piles is relatively low at the same horizontal position of pile 14cm below the pile top, which is inversely proportional to the position of the loading plate and in exponential variation law. Anti-slide pile is the main bearing component of the two supporting structures, and the retaining plank extends the main deformation stage of model damage. The reinforcement effect is obvious. Compared with the anti-slide pile supporting structure, the ultimate load of pile supporting structure is 0.5kN more than that of anti-slide pile, and the bearing capacity of pile supporting structure increases by 14.29%.Distribution form of soil pressure behind the piles is optimized by adopting retaining plank, which makes the soil pressure closer to the end of the anchor and is propitious to resist the flexure deformation of the pile body. This research can provide references for selecting the two different slope supporting structures.