[Objective] To screening mycorrhization helper bacteria (MHB) which were facilitation to the quantity of mycorrhiza and the growing of mycorrhizal seedlings. [Methods] Pinus armandii was an experimental tree species, and eleven bacteria were isolated from rhizosphere soil of Tuber indicum as experimental bacteria. T. indicum inocula and different concentration bacteria were inoculated on P. armandii seedlings. The MHB were ascertained by statistics and analysis of the quantity of mycorrhiza, plant height and ground diameter of the P. armandii mycorrhizal seedlings synthesized by T. indicum. [Results] Pseudomonas sp. JCM 5481 (P143), Streptomyces sp. EN31 (S191) and Variovorax paradoxus (V633) of 2.4×109 CFU/ml had highly significant role in promoting (P<0.01) the quantity of mycorrhiza, plant height and ground diameter, as well as Pseudomonas chlororaphis (P11) and P. corrugate (P127) of 0.8×109 CFU/ml had significant role in promoting (P<0.05) the quantity of mycorrhiza, plant height and ground diameter. Different concentration setting of four Pseudomonas showed each strain has its suitable concentration respectively. [Conclusion] five MHB were obtained in the experiment, and indicated that the concentration of bacteria was a key factor to get MHB.