【英文摘要】Water recycling is a quantitative index for impact of land surface on atmosphere water cycle. While, large uncertanty and disputed exist in this issue by now, especially in Northwest China, where the inner land watershed formed along the unique topography. How much in deed the water recycling in the inner basin is still a key question worthwhile. Several reanalyzed soil moisture data sets for the Heihe River Basin will be assessed based on the remote sensing data and field observations in the first place, And, the best one will be selected as the initializatyion and lower boundary condition for mesoscale atmosphere numerical modeling. The high resolution hydrology-atmospheric coupling model enhanced by Gao et al. will be used, in which the land surface water cycle is included and sutable for complex topography like Qilian Mountain. The spatial distribution of evaporation and precipitation ratio will be modleded through numerical simulation. Finally, the water recycling for the Heihe River Basin will be quanlitatively estimated through the comparison with the sensitive experiments.