This paper reviews the research achievements from Hohai University in mechanics of flow and sediment transport in plain rivers and river treatment practices, including vegetated river flow, flow and sediment transport over rippled beds, hyporheic exchange, river confluences, erosion prevention around piers, sediment deposition prevention downstream of sluices, simulations of flow and sediment transport in complex river networks, and techniques for multi-objective hydraulic control. This paper describes the application of these methods to the solution of many practical problems related to flood and waterlogging control, waterway improvement, and water environment treatment of large- and medium-scale complex river networks in the Yangtze River, Huaihe River, and Pearl River basins. Important issues needed to be concerned in plain river treatment in China are pointed out.