Abstract:This paper deals comparatively with the runoffproducing, soilwater content, water balance and trees growth of two spacing (9m×2m and 5m×2m) artificial Locust Forest between waterharvesting and conventional treatment. The results showed that afforestation by waterharvesting can increase runoff harvest in the planting strip, raise soil water content, permeate more rainwater into deep soil under the roots range and prevent critical deficit of soil water continuously for a long time——soil desiccation, which results in declination of trees growth. In these treatments, the lowest density (8m2 tamped) is desirable for effect, it is that more than 35% annual runoff yield is stored in soil, deep soil water is replenished effectively and growth of forest tress is promoted.