Abstract: In the downstream of the dam,the tail of the stilling pool or the slope of hydraulic structures,the foundation scouring damage often occurs,threatening the safety of the building,so the anti-impact pile is often used to protect the foundation in engineering. In order to explore the anti-impact characteristics of a new type of anti-impact pile,namely non-bearing pile,this paper uses model test method to measure the actual sediment starting velocity of pileless and non-bearing pile at different lengths from 0.06 m to 0.13 m by means of propeller current meters,and compares it with the theoretical starting velocity. Meanwhile,the comprehensive stability coefficient of the pile is calculated. The results show that the longer the pile length is,the greater the actual and theoretical starting velocity of sediment is,and the greater the comprehensive stability coefficient is. In addition,the comprehensive stability coefficient of the pile increases with the increase in water depth. The research results of this paper can provide reference for alleviating foundation scouring and protecting flood discharge safety of river dam.