Based on a large number of measured topographic data,this paper analyzes the characteristics of riverbed evolution in the lower reaches of Xinglong Hub in recent years,and explores the main influencing factors.The results indicate that the riverbed evolution of the studied river section is the result of the combined effects of changes in upstream inflow and sediment conditions,construction of water conservancy hubs and implementation of waterway regulation projects.Under the premise that the upstream water and sediment conditions do not change much and the regulation buildings in the reaches are stable,the overall river regime will remain relatively stable.By analyzing the plane shape,longitudinal erosion and sedimentation,and lateral changes of the studied river section,it is possible to better understand the evolution law of the riverbed in the engineering river section,and provide scientific basis for predicting the evolution law of the riverbed in the lower reaches of Xinglong Hub.