On the basis of the current measurements from the moored Long Ranger ADCP in the upper 450 m layer and the deep current measurements at 2000 and 2300 m from the moored current meters with the time series data of about 7 months at the mooring station in the northeastern South China Sea, the spectral analyses and calculation have been made. The major results are as follows: (i) From the progressive vector diagrams of the observed daily currents at the water levels from 50 m to 400 m, its temporal variation of velocity rotated counterclockwise in most of the observing time. This agrees basically with the result from the qualitative analysis of the sea surface height data, which was obtained from TOPEX/ERS-2 altimeter data by CCAR. The daily and monthly average velocities are both the largest in November, next in October and minimum in August. (ii) At the 2000 and 2300 m levels, the daily and monthly average velocities are both the largest in January, next in September and minimum in August. From the season On the basis of the current measurements from the moored Long Ranger ADCP in the upper 450 m layer and the deep current measurements at 2000 and 2300 m from the moored current meters with the time series data of about 7 months at the mooring station in the northeastern South China Sea, the spectral analyzes and calculation have been made. The major results are as follows: (i) From the progressive vector diagrams of the observed daily currents at the water levels from 50 m to 400 m, its temporal variation of velocity rotated This agrees basically with the result from the qualitative analysis of the sea surface height data, which was obtained from TOPEX / ERS-2 altimeter data by CCAR. The daily and monthly average velocities are both the largest in November, next in October and minimum in August. (Ii) At the 2000 and 2300 m levels, the daily and monthly average velocities are both the largest in January, next in September and minimum in Augus t. From the season