Abstract:An overview of the current status of soil moisture observation stations and an analysis of data quality are conducted in detail, including absolute error and linear correlation between manual and automatic data, the main reason leading to the data errors, and data quality control methods. The results indicate that there are obvious errors between manual and automatic data in some stations during the period of comparative observation, far beyond the acceptance standard of the China Meteorological Administration, and data errors are even above 20% in some stations; however, in nearly 60 percent of stations, the linear correlation coefficient between manual and automatic data exceeds 0.7, which provides an important basis for instrument correction. Also the stability of data in case of drought and precipitation is analyzed, so to present higher quality data on the status of special soil moisture conditions. Considering the actual situation comprehensively, two relatively reasonable data quality control methods of automatic soil moisture measurements are established, which provide support for data quality control and supervision of equipment running status.