It is interpreted in this paper by facts that the worsening of ecosystem in Liaoning Province is the results of irreasonable land use as cultiviting the hillslope strongly，destroying the forest and exessive grazing at mountains in history, which cause vegetation destroyed and soil loss. It mete out severe punishment to human beings themself, such as peoples life and property sustain heavy losses from the mountain torrents frequently. The ability of river channal containing flood-water becomes lower and the reservoir useless because of silting up, and the destroy of vegetation affects,the rainfall and the ability of containing water of soil,so the drought often happens. Fortunately， people are getting better in knowing how important the natural laws are，They depend on the scientific policy and keep the soil and water conservation as their central task.For example, they emphasis.afforestation and grasses, follow the principle of combining the project and biology measures together to harness mountains,land and water comprehen-sively. Now in some places，including Chaoyang area in Liaoning Province，the ecosystem has been improved obviously and quite a good social ands economic effect has been made.