Abstract: The micro lysimeters were employed to determine the process of soil evaporation of winter wheat at its growth stages under sprinkling irrigation condition. Ratios of soil evaporation to evapotranspiration at each growing stage of winter wheat were investigated in the wheat field with different water treatments. The effects of soil moisture and leaf index on the ratio of soil evaporation to evapotranspiration, and the changes of soil evaporation after irrigation were also analyzed. With the analysis of the experiment process and the observation data, the characteristics of soil evaporation were pointed out accordingly; the results also show some merits in making the sprinkle irrigation norm.