Abstract: A soil moisture monitor based on time domain reflection technique(TDR)is introduced in western Liaoning Province to carry out comparison measurement, analysis and error correction on soil moisture monitoring data of 10 cm, 20 cm and 40 cm depth soil layer from May 30 to July 1 in 2019 at Taipingzhuang monitoring station in western Liaoning. The analysis results show that the absolute errors of automatic monitoring data and manual monitoring data of three different depths are all within the range of ±4%, which meets the basic standard requirements of operational operation and can be applied to practical production. The error correction model was established based on the monitoring data errors, the monitoring data of 10 cm and 20 cm soil layer is corrected by unitary quadratic regression equation, and the accuracy of the corrected data is improved by 60.6% and 81.0%, respectively. The monitoring data of 40 cm soil layer is corrected by unary one-step regression equation, and the accuracy of the corrected data was improved by 54.7%, which can better meet the requirements of soil moisture monitoring, and provide scientific basis for the promotion and application of automatic soil moisture monitoring technology in western Liaoning Province.