The dynamic changes of coil water and l,m,"s of water consumption in the field growth wheat with four different till:,ge method were .imulated by the linear regression equation model in arid plain land .lay the linear equation the dynamic change, of soil water are divided into }f stays and the different tillages of wheat have different consuming water amount in the same stage abviosely. The sequence of the water consumption of wheat in whole growth period are as follow,:ridge tillage with stubbe mulch >conservational tillage with stubbe mulch>conservational tillage>ridge. At the same time，the relationship between wheat yield and water consumption amount in earlier growth period is bigger than that in the latter period .the consuming water amount of ridge tillage in earlier stage is bigger than of the conscrvational tillage .and the increasing-yield effect of ridge tillage is responsive to the latter stage of wheat. In order to avoid the consuming water of earlier stage.the ridge tillage should cooperated with stubbe mulch.