By wind tunnel test,the sand preventing mechanism of geo-grid cell sand-barrier,stone-checker sand-barrier and vegetation sand-barrier are studied.The wind velocity profile,wind velocity flow field and structural features of wind sand flows are analyzed.The sand preventing effects of three different sand-barriers are compared.The results showed that the vegetation has prominent effect on wind prevention,and the affection enhanced gradually with the increase of the coverage.Meanwhile,the change of wind speed also related to the luxuriance degree of plants.But to stone-checker sand-barrier,because stone block composing stone-checker is irregular,the experimental result had certain differences on the general regularity.Generally speaking,the protection effect of vegetation is far superior to geocell and stone-checker.To the low wind speed,the geocell and stone-checker is effective,but to the high wind speed,the vegetation is much suitable.For stone-checker and geocell,the protective efficiency of stone-checker is slightly better than geocell.