Abstract: This study aimed to screen multifunctional bacillus strain, to select the efficient combination of different strains and to investigate the mechanism of plant growth-promoting strain. In order to screen multifunctional bacillus strain from 9 candidate strains, the method of flat confrontation, antagonistic activity determination of fermentation filtrate, potted plant growth test, and soil nutrient and soil microbial groups analysis were used. Through the compatibility tests indoor, the optimal combination of functional bacillus strain was obtained. All bacillus strains are found with the function of inhibiting several pathogenic fungi and promoting plant growth except for B02 and B08. B04 is more efficient in promoting plant growth than other strains, and compared to the control, the total dry weights of plant are increased by 28.4% and 44.6% at the days of 30 and 60 respectively. B06 is more effective in inhibiting 8 pathogenic fungi than other strains, with R2/R1 ranging from 0.4 to 1.8, and the inhibition rate of sterile fermentation filtrate is from 66.7% to 87.5%. Besides, B01 has a role of activating N and P, B03, B04, B05 and B06 have a role of activating N and K, B07 has a role of activating K, and B09 has a role of activating N, P and K. The activated rate of N is from 8.4% to 23.2%, the activated rate of P is from 3.5% to 8.4%, and the activated rate of K is from 4.2% to 26.8%. Results of the compatibility tests indoor show that the optimal combinations are B04-B06-B07 and B01-B04-B07. The 9 bacillus strains have one or more than one functions of inhibiting pathogenic fungi, promoting plant growth, activating soil nutrient and improving soil microbial groups. The study of selecting combination of mutifunctional bacillus strain is reliable and feasible. However, application of these strains still needs to be further studied.