Abstract: In order to understand compensatory effect of corn at different growth stages to water deficit changes,the experiment was conducted in field plots.The results showed that compensatory effect is a fundmental capacity in crop life,which can be expressed in three types:yield,growth and physiological action.Under drought at seedling stage and water-recovering at jointing stage,there is a super compensatory effect on plant growth,great yield effect,and physiological effect until tasseling stage of corn.The yield and water use efficiency decrease markedly under drought at tasseling stage,and the yield is the lowest under drought at seedling and jointing stages.