[Objective] To clarity the role of sedimentation and erosion in shaping the spatial pattern of soil quality in black soil slope croplands, this study focused on a typical water erosion area in Northeast China. [Methods]The research aimed to evaluate the spatial characteristics of soil quality at the slope scale by using soil attributes from 110 sample points. The assessment utilized the Soil Quality Index (SQI) based on a minimum dataset, while the effects of slope gradient, slope position, and soil depth were determined using Generalized Linear Models (GLMs). [Results] The findings are as follows: (1) Opposing patterns of soil nutrient content and spatial characteristics were observed between the surface and subsurface layers in sloping croplands. Most nutrient indicators exhibited significantly higher content in the tillage layer compared to the subsurface layer. However, the surface layer showed lower spatial heterogeneity and weaker correlation with related physicochemical indexes comparing with the subsurface layer (p＜0.05). (2) Erosion and sedimentation significantly influenced the spatial distribution characteristics of soil quality. The SQI was significantly lower in slopes with severe erosion compared to up-slope areas with weakly eroded regions and down-slope areas in depositional areas (p＜0.05). Compared with the upper position, the SQI of middle postion was 26.2% and 31.6% lower at surface and subsurface soil layers, respectively. Sedimentation did not improve the soil quality of severely eroded slope croplands, and there were no significant differences in SQI between down-slope and up-slope areas (p＞0.05). (3) Soil depth, slope position, and slope gradient emerged as key factors influencing the variability of SQI in slope croplands. The GLM results demonstrated that, for the same soil horizon, slope, aspect, and their interactions explained over 95-% variation in SQI. Among them, the explanatory degree of slope position was 68%, and that of slope gradient was 22%. Considering the factor of soil depth, the explanatory degrees of soil depth, slope position, and slope gradient on the variation of SQI in the range of 0-40 cm were 39%, 31%, and 10%, respectively..[Conclusion] In this study, the combined method of SQI and GLM was used to clarify the shaping role of erosion-sedimentation process in the spatial differentiation of black soil quality in sloping cropland, and the research results can provide technical support for the evaluation and management of the quality of eroded degraded black soil in typical water-eroded areas.