After receiving precipitation (including throughfall), the exposed rock surface in a rocky desertification area exposed to bedrock is easy to form rock surface flow, which carries organic or inorganic substances on the rock surface to the surrounding soil, having a significant impact on the change of soil nutrients at the rock-soil interface.In this study,three plots, namely fallow land (one-year rock surface flow), abandoned Irrigated grassland (five-year rock surface flow), and sloping farmland (no / little rock surface flow) with obvious bedrock exposure, were chosen in this study to investigate the effect of rock surface flow on the leaching and input of nitrogen and phosphorus in soil at the rock-soil interface.We chose three special shapes of rock surface,namely convex, Straight, and concave, at different horizontal distances from rock surface and soil layer to study the variation characteristics of total nitrogen and total phosphorus in soil at rock-soil interfaces and non-rock-soil interfaces.The results indicated that rock surface flow contributed either input or leaching of nitrogen and phosphorusin 0~10cm surface rock-soil interface soil, but minimally affected nitrogen and phosphorus in 10~20cm deep rock-soil interface soil. The intensity of the leaching and input of nitrogen and phosphorus in the surface soil of rock-soil interface formed by different rock surface shapes was as follows : concave > straight > convex. In the 1-year fallow land, under the action of rock surface flow, the influence of rock surface flow formed by concave rock surface on soil nitrogen at the rock-soil interface was mainly manifested as leaching, while flat and convex rock surfaces exhibited input effects. And the effects of rock surface flow with different shapes on soil phosphorus at rock-soil interface showed leaching. While 5-year rock surface flow showed input.The results can provide scientific basis for further understanding the influence of exposed rock on soil characteristics of karst ecosystem.