Abstract: Objective This paper proposes an original experiential methodology to retrieve bare surface soil mois-ture by two-polarized microwave remote sensing data.In the model,we combined the roughness pa-rameters,the root mean square Sand correlative length L,and introduced a new synthetic roughnessparameter Rsto describe the land surface.So,the unknown parameter in this model reduces to RsandFresnel reflection coefficient in normal directionГ0.Then,Г0and Rscan both be retrieved using two-polarized microwave data.In situ measurements from Heihe experiments were used to test the empiri-cal model.Results indicate that there is a strong linear relationship between the estimated soil mois-ture and the in situ measurements(R2=0.681,RMS=0.043).