Abstract: The nitrogen(N) uptake by 11 maize hybrids in a field trial with three replications at four rates of N supply were researched. Results showed that the N uptake is significantly different among the genotypes. The different of N uptake by grain, straw and biomass of aerial part between highest and lowest genotype in N2 treatment are 1.060,0.134 and 1.125g/kg, respectively, and that in N4 treatment are 0.836,0.154 and 0.954g/kg,respectively. The difference of N uptake by different genotypes in low N treatment is higher than in high N treatment. N fertilizer rate influence the N uptake by the maize remarkably. There is very significant positive correlate between N uptake by grain, straw and aerial part and corresponding outputs of that.