The momentum bulk transfer coefficient and roughness length are calculated by the profile-flux method at  Yingke oasis, Binggou sparse grass, Arou meadow  and  Dadongshu Mountain Yakou snow stations  in upper and middle reaches of Heihe River basin. The results show that the roughness length is related to underlying surface properties and vegetation coverage and height. The maximum and minimum roughness lengths appeared at Yingke oasis station and Yakou snow station, respectively in summer compared with values at Arou meadow station and Binggou sparse grass station. The land cover properties influence the relativity of momentum bulk transfer coefficient on stability. At different stations  the big roughness length is the better relativity of momentum bulk transfer coefficient to stability than the little one.

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