Abstract: In order to compare the water absorption of different trees leaves, the water absorption capacity and water absorption rate of leaves of Robinia pseudoacacia, Ailanthus altissima, Populus simonii, Populus bolleana, Populus hopeiensis, Populus alba×Populus glandulosa were measured by using water immersion method in loess hilly and gully region of Northern Shaanxi. The results showed that: 1) Water absorption capacity of 6 species leaves all increased with immersed time, and their relationship performed as logarithmic function; while water absorption rate decreased with immersed time, performing as power function. The water adsorption rate was the highest within 0-60min after leaves immersed in water, which was the critical stage for leaves to absorb water. 2) The sequences of water absorption capacity and water absorption rate were both as followed: Populus bolleana＞Robinia pseudoacacia＞Populus alba×Populus glandulosa＞Ailanthus altissima＞Populus hopeiensis＞ Populus simonii, the water absorption capacity of P. bolleana and P.simonii leaves were 0.415 and 0.179g/g respectively. 3) On the aspects of water absorption capacity and water absorption rate, P. bolleana leaves were the highest among 6 species, and P. bolleana plays a more important role in crown interception.