Abstract: The responses of A.cacia melanoxylon,A. meamsii,A. implexa, A. dealbata to rhizobial inoculation were reported in this paper. The results showed that the height,total biomass and nodule biomass of inoculation of Acacia with different rhizobium strains were 1.353 8～2.602 6,1.178 5～3.357 9 and 0.022 4～1.026 1 times higher than those of the controls;the height ,total biomass and nodule biomass of inoculation of different Acacia species/provenances with the same sets of rhizobium strains were 0.026 4～1.098 2, 0.018 2～2.814 8 and 0.647 0～2.111 5 times higher than those of the controls. The N concentration and total nitrogen of inoculated seedlings were 0.085 8～0.775 5 and 0.116 4～2.625 0 times higher than those of the controls. Most of the fixed nitrogen by nodules were transported and stored in aboveground than in underground plant parts.A correlation existed between the fixed nitrogen and the height of seedlings.