[Objective] This study aimed to reveal the material transport characteristics and spatial differentiation pattern of wind-blown sand into the Yellow River along the Ulan Buh Desert in the upper reaches of the Yellow River. [Methods] A typical transition zone where the desert directly contacts the river was selected. Based on surface humidity gradients and sediment grain size differentiation, the study area was subdivided into three subregions, i.e. the marginal zone（X1）, transition zone（X2）, and nearshore zone（X3）. The grain size composition and sediment transport characteristics of surface sediments were systematically analyzed. [Results] The marginal zone was dominated by medium-fine sand, with an average particle size of 145.03 μm and strong wind erosion. The transition zone was dominated by sand, with an average particle size of 217.13 μm. The nearshore area was dominated by silt, with an average particle size of 24.95 μm, and the hydrodynamic influence was obvious. The sorting of surface sediments in each region was poor, the skewness was extremely negative deviation-near symmetry-extremely negative deviation, and the kurtosis was narrow-medium-narrow. The proportion of saltation components in the marginal zone was more than 95%, showing a two-stage distribution indicative of long-distance aeolian sand transport. The transition zone was dominated by saltation, and the suspended component accounted for only about 3%. The suspended, saltation, and creep components in the near-shore area accounted for 26.1%, 67.2% and 6.7%, respectively. The contribution rate of 0-10 cm layer was 62%-78%, and the near surface was the core area of wind-blown sand activity. The particle size ranges of the erodible particles in the marginal zone, the transition zone, and the nearshore zone were 170.3-446.5, 137.5-401.2 and 123.6-291.0 μm, respectively. [Conclusion] The marginal zone is the key area for wind erosion control. The wind erosion effect can be weakened and the release of particles can be reduced by setting sand barriers and increasing vegetation coverage.