Abstract: The authors firstly introduce the present situation of water disasters such as flood, water-logging and drought in the San-jiang Plain (Three-river Plain) and analyse their causes of formation from precipitation, landform, rivers, soil to engineering conditions, etc., then put forward elementary suggestions such as strengthening the construction of water conservancy project to control floodwater and enhance the utilization of surface water, plant paddy to decrease water-logging and depress groundwater level, effectively use surface and groundwater by wells, channels and ditches, and adopt the different methods to control different areas, such as plain area, hill area and so on.