The key problem for maintenance and regulation of Yangtze River estuary deepwater channel is the sediment. The paper has measured the reflected spectrums of different suspended sediment concentrations in the Yangtze River estuary deepwater channel sea area where has 7 buoys, and analyzed their spectrum characteristics, in combination with the telemetry data of “ hydrology, sediment and wave automatic telemetry system in the Yangtze River estuary deepwater channel ” and the field survey data. We found that the suspended sediment sensitive band is in 730-930 nm, and the first-order derivative at 731 nm nearby has better correlation with suspended sediment concentration. The suspended sediment exponent model and quadratic inversion model solving spectrum reflectance, spectrum reflectance mean value and reflectance first-order derivative are established respectively, based on the analysis of spectrum characteristics. The results showed that the 900 nm wavelength exponent model can accurately quantitatively inverse the suspended sediment concentrations.