Abstract: Hydroponic experiments were carried out to study the nitrate accumulation of 43 Chinese cabbage genotypes under the nutrient solution of different NO3-/NH4+ ratio. The results indicated that the discrepancies in nitrate contents among different genotypes were significant, and accordingly, Dongfei, Shanghai baiye and Xiayou gaokang as the low nitrate concentration genotypes, and Gaoxiong tiancui, Baoda aiqi, Suzhouqing as the high nitrate concentration genotypes were screened out. Here, the nitrogen source of NO3-/NH4+ 50/50 and the nitrate content in leaves can be considered as the best nutrient solution and index for nitrate accumulation screening. Further study on these six genotypes of Chinese cabbage suggested that the effects of nitrate reductase, maximum nitrate uptake and affinity on nitrate accumulation were significant, while showed different contribution in different part of plants.