[Objective] The quantitative characteristics of plant communities and their influencing factors under different slope positions in the Loess Plateau were investigated, so as to provide a scientific reference for the theoretical understanding of plant community construction mechanisms within the slope-gully system and for the practical guidance on the design of artificially plant communities restoration. [Methods] The study examines the composition, diversity, stability, and distribution patterns of dominant plants across five slope positions-sunny gully, sunny hill, hilltop, shady hill, and shady gully-within the forest-steppe zone of the loess hilly region under natural conditions. The structural equation model of environmental factors, soil erosion intensity, and plant diversity and stability was constructed to explore the main ecological factors affecting the construction of plant communities in different slope positions. [Results] ① In the forest-steppe zone of the loess hilly region, the sunny gully and sunny hill slopes exhibit a two-layer vertical structure predominantly composed of perennial herbs and shrubs, with dominant plants showing a dispersed distribution pattern. The hilltop had a single-layer vertical structure, mainly comprising annual and perennial herbs, where plants demonstrate a highly clustered distribution. The shady gully slope community had a three-layer vertical structure, with plants also showing a clustered distribution pattern. ② The shady gully slope had the highest species diversity, richness, and stability, whereas the sunny hill slope exhibited the lowest richness and diversity, with significant reductions of 18.4% and 26.5%, respectively, compared to the shady gully slope. The hilltop plant community showed the least stability, with an index of only 29. ③ The common key factors influencing community characteristics across different slope positions were soil erosion intensity and soil moisture. However, soil bulk density on the sunny gully slope, organic matter on the sunny and shady hill slopes, and light intensity on the hilltop and shady gully slope were the distinguishing ecological factors affecting plant community structure, stability, and diversity. [Conclusion] Vegetation restoration strategies should be tailored to the specific slope positions in the forest-steppe zone of the loess hilly region. The “fertile island” effect formed by perennial shrubs on the sunny gully slope could improve surface conditions, while micro-topographic modifications on the sunny hill slope could reduce soil erosion. On the hilltop, the introduction of drought-tolerant plants could enhance plant community structure. The shady hill and gully slopes do not require the construction of an excessively complex plant community structure, so as not to cause the degradation of the herbaceous layer under the artificial forest owing to insufficient light.