Abstract: Crop stalks is rich in carbon, nitrogen, phosphorus, potassium, calcium, magnesium, sulfur and silicon etc, it also contains a lot of organic matter such as cellulose, hemicellulose, lignin and protein, crop stalk is a kind of solid waste that can be utilized as resource. Straw residue returned can improve soil, it`s concrete features are that: important source of soil nitrogen; enhance soil retention and buffer capacity; mend physical property of soil; improve the ploughed quality of soil; eliminate pesticide residue and heavy metal pollutions. Further more, the returning can also improve crop quality, protect rural ecological environment, promote the development of ecological agriculture.