Abstract: The objective of this paper was to investigate the effect of ploughed-back green manures on soil physical characters and its corresponding ecological effect by field plot experiment in tobacco-planting dryland soil in west of Hunan Province, as the dryland soil is drought and poor. The results showed that, ploughed-back green manures could improve cycling of material and energy in atmosphere-plant-soil ecological system, fixation of carbon and nitrogen from atmosphere, soil nutrient activation and enrichment, increase soil organic carbon and nutrient input and improve the soil nutrient efficiency, increase soil organic matter, increased by 3.2%-9.5% . Reduce the soil bulk density, the highest pH was lower 0.23 units. In addition, soil physical properties also could be enhanced obviously soil porosity, CEC, water-holding capacity. The largest increase was 6.4%, 21.6% and 3.4% respectively. Therefore, ploughed-back green manures had favorable effect with soil fertilization and ecology, and it could improve soil physical properties.