This paper focused on retrieving soil water content of bare and winter wheat planted field from ENVISAT ASAR image.The relationship between bare soil’s back scattering coefficient and soil water content or land surface roughness was analyzed

and the relationship between winter wheat field’s backscattering coefficient and soil water content or wheat coverage was also analyzed.The result have shown:（1） because bare soil’s backscattering was greatly affected by land surface roughness and soil texture

the positive correlation existed between bare soil’s backscattering and soil water content was not significant

therefore their effects must be considered in the retrieval of soil water content.（2） The difference of sensitivity of two（polarization’s） backscattering to soil water content and wheat coverage was obvious.The difference of the horizontal polarization backscattering coefficients of winter wheat and bare soil was great.Therefore

the horizontal polarization backscattering coefficient was significantly correlated to wheat coverage and soil water content.The vertical polarization backscattering coefficient of winter wheat planted field was sensitive to soil water content.Therefore

the vertical polarization backscattering coefficients was significantly correlated to soil water content

but not significantly to wheat coverage.Combining two polarization backscattering coefficients of winter wheat field

the models between backscattering coefficients and soil water content or wheat coverage were built

and winter wheat coverage and soil water content under wheat canopy were obtained from ASAR image.As expected

the retrieved soil water content and wheat coverage are consistent with those of field measurements.