The aim of this study was to determine the effects of plant species on the potential nutritive value of introduced tree leaves using the chemical composition and in vitro gas production. Gas productions of the introduced tree leaves were determined at 3, 6, 12, 24, 48, 72 and 96 h incubation times and their gas production kinetics were described using the equation y=A (1-exp-(ct)). Plant species had a significant effect on the chemical composition, in vitro gas production, metabolisable energy (ME) and organic matter digestibility (OMD) of the introduced tree leaves. The crude protein content of leaves ranged from 14.16 to 21.92%. The crude protein content of leaves from Robinia poseudoecacia umbraculifera was significantly (P<0.001) higher than those of other legume trees. The NDF and ADF content of legume trees ranged from 30.42 to 41.55 and 27.81 to 28.06% respectively. NDF content of leaves from Gladitsia triacanthos was significantly (P<0.05) higher than those of other legume trees. Although the gas production rate (c) of leaves Albiza julibrissin was significantly (P<0.05) higher than those of Gladitsia triacanthos and Robinia poseudoecacia umbraculifera. The potential gas production of Albiza julibrissin was significantly higher than those for Gladitsia triacanthos and Robinia poseudoecacia. The ME and OMD contents of introduced tree leaves ranged from 9.49 to 10.36 MJ/kg DM and from 64.42 to 70.3% respectively. In conclusion, the species had a significant effect on the potential nutritive value of introduced legume tree leaves. However the tree leaves studied in the current study would be effective protein resource for ruminant animals and may correct the deficient nitrogen in basal roughages with low protein during critical period of year when feed shortage occurred. However leaves obtained from Robinia pseudoecacia umbraculifera, Gladitsia triacanthos, and Robinia psedoecacia should be supplemented with polyethylene glycol or treated with alkali to reduce the detrimental effect of condensed tannin. Condensed tannin (CT) contents of legume trees ranged from 1.70 to 18.35%.