Abstract: The study aimed to find out the effects of different straw returning methods on soil physical properties and spring maize（Zea mays L.）yield.Four straw returning methods were set up： Without straw（S1, CK）, spinning straw into the soil（S2）, plowing straw deeply into the soil（S3） and covering the field with straw（S4）,to study its effects on soil bulk density, soil porosity, soil moisture, soil temperature and maize yield. The results showed that comparing with without straw（CK）, the soil bulk density of 0~40 cm layer decreased by 3.9%, the porosity increased by 2.0%, and the maize yield increased by 2.81% under spinning straw into the soil treatment; The covering field with straw treatment was conducive to improve soil moisture,decreased the soil temperature,maize ear number,grains per spike,100-seed weight,and the maize yield decreased by 3.87%. The plowing straw deeply into the soil treatment increased the soil porosity of 20~30 cm layer, decreased the soil bulk density, increased the field capacity and the soil moisture,increased the maizeear number, grains per spike, 100-seed weight, and the yield increased by 8.24%. Through preliminary study, we found that the plowing straw deeply into the soil can improve soil physical property, and increase maize yield.

Key words: spring maize（Zea mays L.）, straw returning, soil bulk density, soil moisture, yield