Moisture is one of the important parameters in soil polarized spectrum. It has great significance in soil remote sensing band selection and image interpretation; it also provides the information for soil investigation and analysis on physical and chemical properties. In the present paper we tested and analyzed the soil polarized spectrum with different moisture in 350~2 500 nm wavelength range to study on the relationship between soil polarized spectral data and moisture, to determine the spectral response and changes in soil moisture, to establish models between spectral data and soil moisture and select the best forecast model. The results show that the accuracy of the polarized derivative spectra model is higher than the polarized spectral model and absorbance model. All the models showed a water content threshold, and found that it is a certain regularity that critical value of soil moisture in different polarization is near 30%.