[Objective] The resource utilization efficiency and sustainability characteristics of agroforestry systems in hilly and gully loess areas were analyzed to optimize and promote agroforestry production models. [Methods] The theory and method of emergy analysis were used to systematically analyze the emergy input-output structure， environmental carrying effect， and sustainable development potential of four typical complex agroforestry models in Huanglong County， Yan’an City， Shaanxi Province， namely： walnut-purple perilla， walnut-maize， chinese pepper-potato， and Chinese pepper-red bean. [Results] ① All four modes were highly dependent on nonrenewable auxiliary energy （accounting for > 60%）， with fertilizers and mechanical power as the main inputs. The current production mode still relies on petrochemical energy support； The investment in renewable environmental resources accounts for over 24%， with rainwater potential energy and rainwater chemical energy being the main sources. This indicates that local water resources are relatively scarce and that planting relies heavily on natural rainfall. ② Among the four production modes， the contribution of local environmental resources was limited（emergy self-sufficiency ratio， ESR， 0.26~0.31）； The significant environmental pressure（environmental loading ratio， ELR， 1.78~2.35） and overall low net emergy yield ratio （EYR， 1.45~5.90） indicated that the production efficiency and ecological friendliness of the composite system in this region urgently need to be improved. ③ However， the Chinese pepper-red bean model showed outstanding performance， with EYR （5.90）， emergy sustainability index （ESI， 2.55）， and emergy per unit sustainability index （E/ESI， 0.67） were significantly higher than those of the other models and the average for Shaanxi Province. The analysis found that this advantage stems from the multiple ecological functions of red beans as leguminous plants with high solar energy conversion rate， nitrogen fixation efficiency， and resource synergy advantages. In contrast， the walnut-maize model displayed the worst energy utilization efficiency， owing to competition from tall crops. [Conclusion] In the loess hilly region and other similarly ecologically fragile areas， the auxiliary energy structure of agroforestry intercropping should be optimized， and the model of intercropping leguminous plants should be promoted.