Abstract: Acacia mangium seedlings were artificially inoculated with its superior ectomycorrhizal fungus Scleroderma polyrhizum and nitrogen-fixing bacteria rhizobia LR001.After 3 months inoculation,the seedlings could form its typical ectomycorrhiza and nodulation. The result showed that the infection rate of mycorrhiza and nodulation are 100% with higher infection degree. The growth of the seedlings was promoted. The height,ground diameter,fresh weight and dry weight all increased in a certain degree. Dry weight of root biomass underground increased evidently by 430.61% in comparison with the control. One way analysis of variance and multiple range analysis for seedling height indicated that there was an obviously significant difference between inoculation and control.