Abstract: The Holocene profile with palaeoflood slackwater deposit was found in the SJGT reach downstream of the Wuding River basin after a thorough investigation. The palaeoflood SWD is 30 cm thick and contains thin parallel bedding, which directly covers the Eastern Han culture layer. The grain size of palaeoflood SWD is mainly silt with good sorting and low magnetic susceptibility. The mode (Md) and mean (Mz) of palaeoflood SWD are 31.88 and 35.71 μm respectively, which belong to coarse silt. The mode (Md) and mean (Mz) of 2012 flood SWD are similar to those of palaeoflood, and both belong to coarse silt. The sorting coefficients of paleofloods SWD and 2012 floods SWD are smaller, 0.79 and 0.65 respectively, which indicates that they are better sorting in the process of sediment transport. Palaeoflood SWD has sedimentary characteristics similar to those of the 2012 floods and is a Holocene flood geological record. OSL dating of the Eastern culture layer indicates that the palaeoflood occurred between 1 900 and 1 700 a B.P., which is the result of regional response to global climate change. The stage of palaeoflood is 765.86 m by using SWD thickness and sediment concentration method, and the discharge is 15 460 m3/s by using HEC-RAS model method. At the same time, the same method and hydrological parameters (such as roughness coefficient and gradient) are used to simulate the error between the peak discharge of flood and the measured value of hydrological station in 2012, which shows that the selection of parameters and the restoration of peak discharge are reasonable and accurate. The hydrological data of paleoflood are added to the measured flood and historical flood series to establish the relationship between flood peak discharge and frequency at the scale of ten thousand years. The once-in-a-century and once-in-a-thousand floods are transformed from extension to interpolation, which improves the accuracy of flood frequency analysis. Flood peak discharge of once-in-a-century, once-in-a-thousand and once-in-a ten thousand floods in Wuding River Basin are 7 070, 10 820 and 15 710 m³/s, respectively. The results provide important hydrological data for design floods of water conservancy and traffic engineering in the Wuding River Basin.