The study of six crops in three successive years showed that under the same conditions of soil productivity, fertilizer supply and water irrigation, the no-tillage method increased the yield of grain and reduced the production cost by 1. 4%-6. 5% and 23%-44% respectively as compared with the conventional tillage method. The reason for the higher yield lies in that the no-tillage method gave rise to better economic characters of rice than the conventional method. Yet, this advantage is associated with the improvement of the basic physical characters of the soil by the no-tillage method and the consequent improvement of the growth capacity and physiological activities of the root system and the above-ground part.