Concrete structures endure persistent erosion from intense aeolian sand-gravel flows (ASF) in the gravel desert regions with high-velocity winds, which severely compromises their durability. Geopolymer concrete as an excellent green construction material, can be formulated into geopolymer aeolian sand concrete (GASC) through the incorporation of widespread aeolian sand. This method will not only effectively address the erosion phenomenon but also enable the synergistic and efficient utilization of solid waste and local material in deserts. The resistance of GASC to ASF was systematically examined by airflow sand injection method. The results indicate that the erosion rate of GASC first decreases and then increases with progressive aeolian sand replacement. Among the tested groups, GASC with 30% aeolian sand replacement exhibited the lowest erosion rate, showing a reduction of 15.1-18.9% relative to the GASC with 0% aeolian sand replacement. An increase in erosion velocity, erosion angle, sand-gravel flow rate, and cumulative erosion time elevates the erosion rate of GASC, but decreases as the erosion particle size (EPS) increases. The erosion rate of GASC displays a negative linear relationship with compressive strength and splitting tensile strength, and a positive linear relationship with total porosity and porosity of large pores, with fitting accuracy R2 values exceeding 0.88 in both cases. When the aeolian sand replacement remains below 50%, it refines the pore structure of GASC, reduces stress concentration at the surface, and consequently inhibits material spalling. In addition, under erosion action, smaller gravels tend to produce deeper erosion pits, whereas larger gravels result in relatively shallower erosion pits. Based on established erosion models and predictive equations, this study introduced a compressive strength function and an EPS function to improve the erosion model tailored for this material. The improved E/CRC model demonstrated more stable predictive performance, with prediction accuracy R2 values consistently above 0.86. This study offers guidance for the erosion-resistant design of GASC in gravel desert environments.