The characteristics of soil and water loss in block-type engineering and line-type engineering were analyzed by making soil and water conservation plan for some large and medium-sized projects.The analyses indicate that the quantity of soil and water loss in the construction period is 85%of the total soil and water loss.The quantity of soil and water loss of perunit area in block-type engineering is 86.61 t/ hm²and the quantity of soil and water loss perunit area in line-type engineering is 202.40 t/hm².The quantity of soil and water loss and the area in the construction period of block-type engineering have a linear relation(R²=0.9497).The relationship betw een soil and water loss and the area in the construction period of line-type engineering is logarit hmic(R²= 0.8003).Furt hermore,some cases in the study show that it is need to calculate the reduced quantity of soil erosion by choosing the rate of reduced quant ity of soil erosion for forestry and grass measures.