［Objective］ The effects of different straw return methods on soil structural properties and the relationship between organic carbon and aggregate stability were investigated， in order to provide a theoretical basis for implementing effective erosion control techniques on sloping farmlands in black soil regions. ［Methods］ Natural soil aggregate breakdown mechanisms were simulated to analyze changes in aggregate stability under straw return practices. ［Results］ The stability of soil aggregates varied depending on the breakdown mechanism and straw return method. Rapid wetting was identified as the primary mechanism for aggregate breakdown in black soil. Significant differences in mean weight diameter were observed for <2 mm and 2—5 mm aggregates under rapid wetting and wet shaking mechanisms. The 2—5 mm aggregates under wet shaking exhibited the highest stability， indicating that larger aggregates in black soil were more stable and positively correlated with soil organic carbon. For <2 mm aggregates under wet shaking， stability was significantly positively correlated with soil bulk density and capillary porosity but negatively correlated with total porosity and non-capillary porosity. ［Conclusion］ In the short term， straw mulching may obscure its erosion control effects due to abiotic factors such as soil bulk density and porosity， thereby influencing aggregate stability. In contrast， straw incorporation reduces the total porosity and non-capillary porosity while tending to enhance aggregate stability.