Abstract: In light of the widely accepted principles of sustainable development, optimizing the utilization of crop straw and human-livestock-poultry manure has emerged as a crucial goal. Agricultural production and lifestyle are constrained by topography, causing notable disparities in the composition, distribution, and environmental benefits of crop straw and manure in areas with different topographic characteristics. Differential analysis is therefore needed to lay the foundation for targeted development of sustainable utilization and management strategies for organic wastes. In this study, Anhui Province serves as a typical research case. Initially, the dissimilarities in the production scale and structural composition of crop straw and manure across three distinct topographic types in Anhui Province including plains, hills and mountainous regions are systematically assessed using methods such as structural difference index. Subsequently, by comparing nutrient supply and demand relationships, the potential contribution of straw and manure to fertilizer substitution is analyzed. The results demonstrate that from the perspective of inter-regional nutrient structure difference index, the nutrient structure difference indices of N, P₂O₅ and K₂O in the plain-mountain comparison group are the highest, with 0.86, 0.84, and 1.13, respectively, while that in the hill-mountain comparison group are the lowest, with 0.26, 0.25, and 0.25, respectively. In terms of regional considerations, it is only in hilly areas that recycled straw and manure can completely substitute chemical fertilizers in supplying essential nutrients required for crop growth, while plain regions are inadequate in providing N and P₂O₅, and mountainous areas are deficient in P₂O₅. With respect to nutrient types, although the amount of K₂O needed for crop growth is more than that of N and P₂O₅, K₂O is the only nutrient that can be fully satisfied by reusing straw and manure in all regions with different topographic characteristics. Additionally, the nutrient structure compositions of hilly and mountainous areas remain relatively similar, and there is a significant difference compared to plain areas. In particular, the source difference of nutrient-K₂O in different topographic areas is the greatest. Overall, the reuse of straw and manure can supplement the nutrient needs of farmland, but it cannot completely replace the use of fertilizers except in hilly areas. The planting and breeding structure in hilly areas can provide significant reference value for future industrial adjustments in various regions.