Abstract: In order to study the difference of nitrogen absorption and utilization of different tobacco genotypes, and to provide theoretical basis for nitrogen high efficient cultivation and breeding of tobacco, 74 tobacco genotypes were treated with hydroponics in low nitrogen (0.5 mmol/L) and high nitrogen (5.0 mmol/L) levels at the seedlings stage. The difference in nitrogen use efficiency of different tobacco genotypes was studied by using descriptive statistics of nitrogen nutrition indexes, nitrogen use efficiency and division of different types of nitrogen nutrition. The results indicated that there was significant difference in nitrogen use efficiency between different tobacco genotypes, and the interactions between genotype and nitrogen level were significant. Based on the above ground biomass, the nitrogen efficiency of different tobacco genotypes could be divided into 4 types:efficient, low N efficient, High N efficient, and inefficient. Under different nitrogen levels, the direct effect of nitrogen uptake efficiency on nitrogen efficiency was greater than nitrogen utilization efficiency. At low or normal nitrogen levels, the aboveground biomass, plant nitrogen accumulation amount, nitrogen uptake efficiency, nitrogen use efficiency of the nitrogen inefficient genotypes were significantly lower than that of the nitrogen efficiency genotypes, but the differences of nitrogen utilization efficiency were not significant between the genotypes. Nitrogen absorption ability is therefore very important for breeding and cultivating nitrogen efficient tobacco.