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With the method of artificial soil columns, several kinds of soil, such as loam, clay, and sandy soil, were used in the FDR (Frequency Domain Reflectometry) moisture sensor calibration experiment to analyze the relationship between sensor frequency and soil moisture. The effects of soil textures on calibration parameters are studied through calibration experiments on different kinds of soil. The results show that the frequency of the FDR soil moisture sensor is monotonously decreasing with the increase of soil volumetric water content; the correlation is obvious, and different kinds of soil affect moisture sensor parameters remarkably. The normalized frequency of the sensor for clay testing ranges between 064 and 094, loam between 04 and 086, soil between 03 and 094 A better result is obtained in classification calibration than in concentration calibration. The experimental results have significance for the fine calibration of automatic soil water detectors in the areas with complex soil.