The phenomenon of backwater is commonly observed in major rivers and lakes worldwide,often leads to upstream water stagnation and increasing the risk of flooding during high-water periods,which threatens lives and property of people living along the riverbanks.The complex variations in river flow movement characteristics caused by backwater effect,influenced by numerous factors,studying its hydrodynamic patterns and impacts is crucial for flood control,port and waterway development,and comprehensive basin management.We preliminarily analyze and summarize domestic and international research findings in this field,focusing on three aspects,such as the fundamental characteristics and influencing factors of rivers affected by backwater,the hydrodynamic responses of rivers to backwater,and methods for quantifying the degree of backwater influence on water flow.Additionally,we analzye research gaps and trends,propose key directions for future research,which can provide insights and references for studying river flow movement characteristics under backwater effect and comprehensive regulation.