Abstract: In order to provide better approach for the automatic evaluation of soil moisture observation data of Jiangsu Province and to provide references for processing when there is significant deviation in the automatic soil moisture observation data, in order to improve the automatic soil moisture observation data to be more accurate and more representative. This research is based on the data of manual and automatic soil moisture observation in two waves of March and April of 2012 in Jiangsu Province, and it makes emphasis field research and analysis to the stations that have significant deviation with the soil moisture observation data. The results show that: when processing comparison observations of manual and automatic soil moisture, people should analyze whether there is exception of the average absolute error value of the soil moisture at different levels when the total average absolute error value of soil moisture is relative large. If there are exceptions at different levels, it needs to analyze whether there are exceptions in the correspondent four weight of soil water content of the manual soil moisture observation. The average absolute error value of soil moisture observation in Jiangsu Province being relative high is mainly due to soil differences, and secondly because of instrument and man-made measurement reasons. Therefore, site selection and observation with specifications are particularly important.