It is generally known that in order to make the stiff clay gradually become chessom,we can make use of green manure to bring into practice the reclamation of physico-chemical properties of soil,the decrease of bulk density and resistance to compression of soil and the increase of porosity,moisture capacity and aggregation of soil. In addition,application of green manure evidently accumulates some additional organic matter and nitrogen contained in the soil.It should be noted that the response of rice productivity on mixed cropping of vetch-rye grass used as green manure is much better than vetch alone.