[Objective] Land preparation is a key measure in agricultural production in hilly and mountainous areas. It is of great significance to clarify the response relationship between the changes of soil properties after land preparation and the spatial variation characteristics of soil moisture in the field for improving the efficiency of agricultural production. [Methods] Two typical land preparation measures，i. e. horizontal and reverse slopes in hilly and mountainous areas of Guangxi，were taken as the research objects. Field radar detection experiment was combined with indoor soil analysis tests， and the effects of land preparation measures on the variation characteristics of soil moisture in sloping farmland were discussed in depth by means of image analysis and statistical analysis. [Results] Under the same external water supply conditions，the spatial variation of soil moisture after horizontal land preparation significantly occurred in the 0―30 cm soil layer，that after reverse slope preparation was concentrated in the 20―40 cm soil layer，while sloping farmland exhibited moisture variation throughout the entire 0―50 cm soil layer. The spatial distribution of soil moisture in the field of horizontal land preparation was the strongest（average deviation degree 0.052），and the change degree of land preparation on the reverse slope was the weakest. The spatial movement of soil moisture in the field of horizontal land preparation was stable（reflection coefficient 0.33，instantaneous power change rate 8.41×10¹¹ dB/ns）and relatively uniform （radar structure similarity index 0.77），while the degree of soil moisture movement in the field of reverse slope land preparation and sloping farmland was more intense，and the spatial movement state changed greatly. The spatial variation of soil moisture in sloping farmland was the largest（comprehensive index 1.45），followed by reverse slope preparation（comprehensive index 1.53），and the spatial variation of soil moisture in horizontal preparation was the smallest（comprehensive index 1.57），and the soil moisture environment was relatively stable. Compared with sloping farmland，the soil silt content after land preparation had the greatest influence on the spatial variation of soil moisture. [Conclusion] Under the same external water supply conditions，the soil moisture condition in the field after horizontal and reverse slope land preparation is better than that in sloping farmland，and the soil moisture storage condition in the field after horizontal land preparation is better.