Abstract: The changes of discrepancy between canopy and air temperature of wheat under different soil moistures from jointing to heading stage were analyzed.The results indicated that the change of discrepancy between canopy and air temperature was smooth under full water supply,and its change was large under water deficiency.The change tendency of discrepancy between canopy and air temperature with growth stage was higher under water deficiency than full water supply.The discrepancy between canopy and air temperature can be an indicator used for evaluating the change of soil moisture and the degree of crop water deficiency