Abstract:TDR soil moisture instrument(model ET-FOM/mts,made in Poland)was calibrated for two types of soil of different texture in Fengqiu region under different treatments of temperature and bulk density.The result show that the relationship between the square root value of dielectrical constant of soil and soil water content in volumatric basis can be well described by linear equations of which the correlation coefficient are equal to or greater than 0.997.Regression errors of the calibration curves range from 0.002 to 0.027 cm3 cm-3,and sandy loam soil shows the smallest error at low temperature(16℃),while the biggest error occurs when loamy clay soil is measured at high temperature(26℃).