Abstract: The concentrations and spatial distribution characteristics of the transferable nitrogen (TF-N) including ion-exchangeable form (IEF-N), carbonate form (CF-N), iron-manganese oxides form (IMOF-N) and organic matter-sulfide form (OSF-N) in the sediments of the coastal waters of Bohai bay were studied by the sequential extraction method, and further to reveal their environmental significance. The results showed that the concentrations of TF-N in the surface sediments ranged from 145 μg/g to 233 μg/g, with an average value of 193 μg/g. Affected by terrestrial sources, the overall distribution characteristics of nearshore content were higher than far shore; the proportion of nitrogen forms in TN was: IEF-N (9.6%) > IMOF-N (4.4%) > OSF-N (3.9%) > CF-N (0.08%), and their spatial distribution was different. The vertical variation range of TF-N concentrations was 24 ~ 313 μg/g, and the vertical distribution varied in different research sites. IEF-N and IMOF-N in TF-N showed an increasing trend with increasing deposition depth, OSF-N had different vertical distributions at different stations, the concentrations of CF-N was the smallest, and its vertical change was not significant. According to the sediment quality assessment guidelines, TN in the sediments in the study area was at the lowest level; The absolute contributions of various forms of nitrogen after being completely released according to binding capacity to the overlying water were as follows: IEF-N (44.4%) > OSF-N (35.4%) > IMOF-N (19.7%) > CF-N (0.5%).