Abstract: Existing watershed partitioning methods are suitable for areas with clear elevation differences while are less applicable in plain river network areas.To solve the problem of watershed partitioning in the plain river network area, a multi-scale and hierarchical watershed partitioning method in the plain river network area was proposed.Referring to water systems, roads, dikes, gates and pumps, and land use types, and combining with cell-level grid and grid centroid spatial analysis data, we generated a reference map for watershed partitioning.The proposed method was applied to the plain river network in Zhonglou District, Changzhou City by establishing a HSPF hydrological model of this area.The results showed that the simulation results of hydrological processes in Zhonglou District from 2020 to 2021 were good, and the correlation coefficient and Nash coefficients of the stations at the Deshenghe Bridge, Zhonglou Bridge and Lianjiang Bridge were greater than 0.75,which satisfy the model simulation accuracy.The proposed method of watershed partitioning in plain river network is reasonable and feasible.