[Objective] The effects of a long-term Caragana korshinskii plantation on the stability of soil aggregates and erodibility on loess hilly slopes were determined, in order to provide theoretical support for artificial vegetation construction and ecological restoration in the Loess Plateau region. [Methods] A barren grassy slope was compared with C. korshinskii plots of different plantation ages (15, 25, 35 years) along similar slope contour lines. the characteristics of changes in soil aggregate stability and erodibility due to a long-term C. korshinskii plantation was analyzed, as well as the main influencing factors. [Results] ① The soil aggregate stability indicators 〔i.e., mean weight diameter (MWD), geometric mean diameter (GMD), and the content of aggregates ＞0.25 mm (WR_0.25)〕 generally followed the order of 15-year C. korshinskii plantation ＞ barren grassy land ＞ 25-year C. korshinskii plantation ＞ 35-year C. korshinskii plantation. In terms of slope position, the order was bottom slope ＞ top slope ＞ mid-slope ＞ upper slope. Conversely, the soil erodibility K factor exhibited an opposite trend. ② As C. korshinskii plantation age increased compared with barren grassy land, soil aggregate stability indicators initially increased and then decreased, while the stability of barren grassy strips continuously declined. The difference between the two became more pronounced after plantation age exceeded 15 years, especially at the bottom slope. ③ Soil organic carbon and slope position were the main factors influencing soil aggregation stability and erodibility on the slope, explaining 38% and 4.1% of the variation, respectively, followed by plantation age and altitude. [Conclusion] Strip planting of C. korshinskii on loess hilly slopes affected the distribution of soil organic carbon, thereby influencing soil aggregate stability and erodibility. Plantations of less than 15 years contributed to an increase in soil aggregate stability and a reduction in erodibility, but a reverse trend gradually emerged with older plantations, particularly at the bottom slope locations.