Mulan river is a plain alluvial river，the river slope is mostly alluvial silt in certain conditions，the formation of consolidation in fall，the stability problem of the erosion and collapse to river bank soil contact boundary for two yuan；to build a green ecological river，summarized the Mulan River Basin of Putian River Soil Characteristics and potential instability.Recommended the use of the tree stump and rockfill slope protection method for flexible solid bank building green ecological river.The stump of rockfill-a flexible way to protect the river slope，deep roots with root anchoring effect，shallow root reinforcement effect；the establishment of a healthy ecological system，minimizing the original environment and Terrain Influence and destruction；add green landscape，landscape effect significantly.