Abstract: The Physiological functions among maize genotypes with different tolerance to drought in the field condition were dissimilar.This paper described the component difference of bleeding sap among maize genotypes with different tolerance to drought.A field experiment was conducted to investigate the content of nitrate nitrogen,ammoniacal nitrogen,phosphorous,kalian and calcium of bleeding sap and its difference with two genotypes Yedan-13 and Danyu-13 during seedling,jointing,booting and filling stages.The results showed that compared with the roots of non-drought-tolerant line root system,content of nitrate nitrogen of bleeding sap at jointing,booting and filling stages was significantly greater(p<0.05),content of kalian of bleeding sap at seedling,jointing,booting and filling stages was significantly greater(p<0.05),content of ammoniacal nitrogen,phosphorous and calcium of bleeding sap had no significant differences(p>0.05).