Dongliu reach of lower Yangtze River is a typical multi-branched shoal reach and faces difficult regulation. Based on the measured data over the years, this paper analyzes the evolution law of beach groups in Dongliu reach. The results show that part of the riverbed in Dongliu reach has changed greatly after a flood in 2020. Specifically, lower bank slopes of Huayang Sluice on the left bank have collapsed in a wide range, and the elevation on the head of Mianhua shoal has cut down and tended to separate from the fish-bone dam project. In addition, the evolution of shoals and beaches is unfavorable. Therefore, the paper suggests that the bank slope on the left bank of the inlet reach should adopt measures to protect the project, and the project for protecting the head of Mianhua shoal should expand its application range, so as to restrain the flow scour on the beach surface and ensure the long-term stability of the multi-branched and water-diversion pattern of the reach.