Based on the investigations in February and August, 2004 in the Yangtze River Estuary, the concentration distributions of nitrate (NO₃-N), ammonium (NH_{4-N) and phosphate (PO4-P) in the bottom and surface layers are presented for analysis. It is found that the concentration of the new nutrient (nitrate) shows the high level near the coast and gradually decreases toward the continental shelf in two seasons; whereas the concentration of the regenerated nutrients (ammonium and phosphate) show the high level in the bottom layer comparable to that in the surface layer in summer. Since the phytoplankton is the most active in summer, the nutrients in the upper layer are consumed largely due to the photosynthesis. In the meanwhile, the nutrients regenerated on the sea floor can reenter the bottom layer of the water column and make up the nutrient content. Therefore, the concentrations of regenerated nutrients are higher in the bottom layer than that in the surface layer. In winter, the nutrients are distributed in the similar way in the surface and bottom layers due to the strong vertical mixing in the water column. The further research on the nutrient limitation, according to the Redfield theory, shows that the phosphorus limitation dominates in the river mouth, and such a trend gradually shifts to the nitrogen limitation toward the continental shelf. The variation of the nutrient limitation may be dependent on the relative strength between the Changjiang diluted water and the intrusion branch of the Kuroshio Current.}