In order to evaluate the hydrological functions of dwarf bamboos，the water holding capacity and the rainfall interception rates of four dwarf bamboos，such as Arundinaria argenteostriata，Arundinaria fortunei，Shibataea chinensis and Sasaella masamuneana were investigated． The results show that the litter volumes of Arundinaria argenteostriata，Arundinaria fortunei，Shibataea chinensis and Sasaella masamuneana were 4． 51，4． 33，6． 32，and 6． 67 t/hm²，respectively． The maximum water-holding volumes of these four dwarf bamboo litters ranged from 12． 77 to 16． 66 t/hm²． The rainfall interception rates of the litters were closely related to the thickness and their water contents，and the interception rate of the litter with 1 cm thickness was significantly different from that of the litter with 3 cm thickness．With the increment of litter thickness，the interception rates increased when the litter water contents were 50． 81% ～66． 27%． The 3 cm litter intercepted more rainfall than the 1 cm litter，by 126%，51． 4%，114． 3%，and 56% more for Arundinaria argenteostriata，Shibataea chinensis，Arundinaria fortunei and Sasaella masamuneana，respectively．