Abstract:【Objective】During the production and construction processes in North Shaanxi, large stacks of soils formed, triggering serious soil and water losses. The existence of gravels in the stack is an important factor affecting the soil erosion in characteristic. Therefore, this study was oriented to explore impact of gravel concentration on runoff and sediment yielding processes on slopes of the gravel-containing aeolian sand stacks. 【Method】In this study an indoor simulated rainfall experiment was carried out on stacks. The experiment was designed to have three levels of gravel concentration (10%, 20% and 30%), four levels of rainfall intensity (1.0 mm?min-1, 1.5 mm?min-1, 2.0 mm?min-1 and 2.5 mm?min-1) and one pure soil slope (containing zero gravel) as control. The experimental plots were 5 m × 1 m × 0.5 m each in size and laid on slopes 25 ° in gradient. The nozzles of the rainfall simulator were 18 m high above the ground, providing artificial rainfall over 80% in uniformity. Rainfall intensity was determined before the start of each artificial rainfall event to ensure the artificial rainfalls < 5% higher or lower than the designed one. During the experiment, flow velocity of runoff on the slope was measured with the dyeing method, flow width measured with a steel ruler, duration of sediment pooling recorded with a stopwatch, and mass of the sample determined with an electronic scale. 【Result】Results show: (1) Under artificial rainfalls, 1.0, 1.5, or 2.5 mm?min-1 in intensity, runoff rates were 5.03% ~ 39.99% lower on the slopes 10% in gravel concentration than on CK, but 7.48% ~ 74.56% and 19.51% ~ 84.31% higher on the slopes 20% and 30% in gravel concentration, respectively; runoff rates on all the slopes increased with rising rainfall intensity, displaying an exponential function relationship; (2) Runoffs on all the slopes formed laminar flows; on CK runoffs rushed a bit, while on the slopes containing gravels they flew slowly; Under rainfalls varying in intensity, drag coefficients of runoffs on slopes, 10%, 20% and 30% in gravel concentration increased by 24.07% ~ 114.10%, 51.84% ~ 141.57% and 89.04% ~ 288.16%, respectively; (3) Under rainfalls 1.0 and 1.5 mm?min-1 in intensity, soil erosion rate on CK and the slopes 10% in gravel concentration displayed a variation trend with rainfall going on, i.e. decreasing – stabilizing – increasing, and under rainfalls 2.0 and 2.5 mm?min-1 in intensity, it fluctuated more vigorously; Under rainfalls regardless of intensity, soil erosion rate on the slopes 20% and 30% in gravel concentration decreased slowly and then increased steadily; (4) Under rainfalls 1.0 mm ?min-1 in intensity, CK was the lowest in soil erosion rate and under rainfalls ≥ 1.5 mm ?min-1, soil erosion rate decreased by 41.08% ~ 63.27%, 22.80% ~ 67.80%, 28.89% ~ 68.50% on the slopes 10%, 20% and 30% in gravel concentration, respectively; (5) Soil erosion rate was significantly and positively related to runoff rate, Reynolds number, and Freud number, but negatively to drag coefficient. 【Conclusion】All the findings in this study will provide a theoretical basis for establishment of a model for predicting water and soil losses of engineering stacks of aeolian-sand soil in North Shaanxi.