Straw mulching and residue practices have great influence on growth and water consumption of summer corn.It can reduce soil water evaporation in early stages and increase crop transpiration in late stages.These are benefits to dry matter accumulation and yield increasing and water use efficiency of corn.The effects of straw mulching and residue are different under different soil water conditions.The increasing of yield and water use efficiency reduce with increasing of soil water content.It demonstrates that straw mulching and residue practices are applicable in arid and semi arid regions.It is significant for developing dry land farming in North China.