Abstract: Effects of different management technology on underground water level,volume of forest tree growth and root growth amount were studied.The results showed that all the treatments of high ridge and low ditch,shallow planting of cutting root,and integrated disposal of ditching and cutting root could reduce the underground water level and promote the growth and development of trees.Among which,the effect of integrated disposal of ditching and cutting root was the best and was the suitable management technology for constructing Jiangnan alnus forest in water wetland where suitable to grow forestry in mountainous area.