Abstract: In the southwest China,a series of negative groove terrain were often developed on the slope of rivers valleys.These landforms have a sort of pattern:upper wide and narrow lower.In other words,they show that the upper U-shaped canyon and slightly open,then lower valley narrowed has been connected to the river valley edge.The topography of its upper negative groove terrain elevation is around (1?500)～(2?000) m in generally.In the last survey of geological disasters,this phenomenon is often considered as landslide accumulation landform.In this paper,we analyzed the valley slope groove accumulation deposits in the Jinshajiang River of a hydropower station,and proposed the causes and stability evaluation results from the perspective of geological analysis.Finally,according comparative study,the causes of accumulation are related to the processes of ice and snow,and its stability has impacting on the safety of the surrounding construction in varying degrees.