Understanding the molecular mechanism of the genotypic differences in nitrogen use efficiency of wheat is very important for the molecular breeding of Nefficient wheat varieties.Seasonal expression patterns of five genes(TaGS1c，TaGS2a，TaAlaAT，TaASN1 and TaPPDK)involved in nitrogen(N)metabolism in two wheat genotypes with high and low nitrogen utilization efficiencies of winter wheat were investigated.Shoots were sampled at the tillering,jointing,heading,grain filling and harvest stages.The results showed that the grain nitrogen utilization efficiencies of wheat genotype XY107 was greater than that of LM1 in both LN and HN treatments;The expression levels of the three genes TaGS1c,TaAlaAT and TaPPDK in the Nefficient wheat genotype XY107 were significantly greater than that in LM1 after the heading stage in the low N treatments;Only the expression levels of the genes TaPPDK was significantly enhanced after heading stage and in the Nefficient wheat genotype XY107 were significantly greater than that in LM1 in the high N treatments.The present study suggested that the genes TaGS1c,TaAlaAT and TaPPDK might play important roles in determining the genotypic differences of the nitrogen use efficiency of wheat.