In order to explore the characteristics of slope surface microtopography(SSM) change of slope farmland under different artificial management measures, and clarify the response of SSM change to seepage, so as to provide a scientific basis for the effective prevention and control of soil erosion and the reasonable layout of artificial management measures, this study took the flat slope (CK), artificial digging slope (AD) and ridge tillage slope (RT) as the research object. Based on simulated seepage experiment, the variation characteristics of SSM on 5° and 15° purple soil slopes were studied. The results showed that (1) The semivariogram of SSM on the three slopes showed a central symmetric distribution in the directions of 0~135° and 180°~315° before and after the seepage test, and the distribution range gradually decreased with the increasing of slope gradients and exhibited obvious directivity. Under seepage condition, the variation trend of SSM anisotropy on CK and AD was relatively consistent, while the spatial variability of SSM on RT was strong. (2) Under seepage condition, the range of elevation variation on the three kinds of slopes was mainly concentrated in -20 mm to 0 mm, and the distribution of slope elevation of relative rough slopes (AD and RT) was more dispersal compared with CK. (3) Compared with 5° slope, the response of soil surface roughness (SSR) change to seepage was more obvious on 15° flat slope. The change rate of SSR followed the order of CK>AD>RT. Under seepage condition, the SSR varied greatly at the midslope and downslope. The more intense the initial fluctuation of slope surface was, the more obvious the abrupt change response of SSM to seepage erosion. In this study, soil surface roughness could be used as an indicator for describing the response of SSM changes to seepage condition, which could efficiently characterize the spatial distribution of soil erosion-deposition at the middle and downslope, so as to provide a theoretical basis for clarifying the coupling relationship between the variation of SSM and seepage erosion on purple soil slope.