Abstract: To analyze the effects of plant growth-promoting rhizobacteria (PGPR) on the quality improvement and yield increase in flue-cured tobacco, three bacterium strains, indole-3-acetic acid (IAA) producing bacteria, phosphate solubilizing bacteria and potassium solubilizing bacteria, which possessed better promoting and non-antagonism activities were isolated from tobacco rhizosphere soil in Panzhihua. The three strains were mixed to prepare multi-function PGPR microbial inoculant, pot and field experiments were carried out to study the effects of multi-function PGPR microbial inoculant on the quality improvement and yield increase in flue-cured tobacco. The results showed that the multi-function PGPR microbial inoculant improved agronomic traits of flue-cured tobacco and chemical quality of tobacco leaves, and decreased the incidence of tobacco diseases. In the treatment of compound fertilizer as base fertilizer combined with multi-function PGPR microbial inoculant, the middle and high grade proportion of tobacco leaves significantly increased by 22.0%. In the treatment of compound fertilizer and organic fertilizer as base fertilizer combined with multi-function PGPR microbial inoculant, the middle and high grade proportion of tobacco leaves and output value significantly increased by 34.5% and 26.4%, respectively.