Spatial variability of soil moisture on micro-topography is an important factor influencing the distribution and restoration of vegetation on the Loess Plateau of China. Soil moisture of different size of platforms in loess hilly-gully region was investigated and analyzed. The results showed that: (1) The size of platform had a significant impact on soil moisture content. Overall, the larger platform showed a better soil moisture condition; (2) The variation coefficient of soil moisture in 0-60 cm soil layer of platforms ranked as follows: small size platform(<100 m²)> large size platform(>1000 m²)> medium size platform(100~1000 m²); (3) Within the large size platform, the variation coefficient of soil moisture along the up and down slope direction(parallel to slope) was higher than that along the contour. Geo-statistics was used to analyze the spatial heterogeneity of soil moisture(0-60 cm) in large size platform. A spherical model was used to fit the change of semi-variance with separated distance. Kringing interpolation showed that within the large size platform, soil moisture on the joint part of platforms and the scarp on upslope was higher than other parts.