Abstract:[Objective] This study aims to investigate the effects of wind-rain complex erosion on soil aggregate organic carbon in the Loess Plateau. [Methods] Laboratory-based rainfall simulation and wind tunnel experiments were conducted to study the loss mechanisms of organic carbon and its labile fractions in 5-2 mm soil aggregates under different erosion forces and erosion sequences. [Results] 1) Under wind-rain complex erosion, the mass fractions of soil aggregate organic carbon(SOC), easily oxidizable organic carbon(EOC), particulate organic carbon(POC), and dissolved organic carbon(DOC) decreased by 7%-25%, 8%-29%, 52%-71% and 16%-32%, respectively, compared with single-force erosion. 2) Under wind-rain complex erosion, the mass fractions of SOC, EOC, POC, DOC, and microbial biomass carbon(MBC) under wind-then-rain erosion(WR) decreased by 19%, 20%, 4%, 13% and 9%, respectively, compared with rain-then-wind erosion(RW). 3) Aggregate organic carbon and its labile components exhibited different sensitivity response to different erosion forces: EOC showed higher sensitivity to rain erosion, while POC was more sensitive to wind erosion and wind-rain complex erosion. [Conclusion] Wind-rain complex erosion more significantly exacerbates the losses of aggregate organic carbon and labile organic carbon fractions compared to single-force erosion, and the degree of SOC loss shows dependence on erosion sequence. These findings provide theoretical support for developing soil erosion prevention and organic carbon sequestration strategies in regions affected by wind-rain complex erosion.