The national key ecological function zone of windbreak and sand fixation type (NKEFZ-WSF) is the main sand-proof barrier belt in China, which is of great significance for protecting the ecological environment security of the whole country. This study simulated the spatio-temporal patterns and flow trajectories of the wind erosion prevention service (WEP) in NKEFZ-WSF based on the Revised Wind Erosion Equation (RWEQ) and the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model, respectively, and constructed the spatio-temporal paths connection between NKEFZ-WSF and its service beneficiary areas (SBAs) of WEP. The results indicated that the total amount of WEP in the NKEFZ-WSF was 5.55×10¹² kg in 2010 and can benefit the SBAs of 32.16×10⁶ km², involving 755 flow paths of the WEP. The SBAs were mainly located in the vast areas of Northwest, North and Northeast China, the Korean Peninsula, Japan, Russian Far East and the vast sea areas of the North Pacific Ocean, of which the SBAs within China accounted for 24.12% and the benefiting grassland was the largest. Besides, the proportion of benefiting construction land in China's total construction land was the highest with more obvious benefits transferred. In terms of spatial distribution, the flow benefits of the WEP had the obvious feature of decreasing in the circle type centering on each NKEFZ-WSF. The WEP flows of NKEFZ-WSF play an important role in guaranteeing the production and living quality of the downwind SBAs. This study can provide a scientific reference for the formulation of interregional ecological compensation policies for NKEFZ-WSF, so as to further enhance its barrier effect of wind prevention and sand fixation and safeguard the national ecological security.