[Object] The characteristics of the plant growth promoting Bacillus spp. in a feldspathic sandstone soil were investigated in order to provide resources and technical information for feldspathic sandstone soil improvement.[Methods] Bacillus spp. was isolated from plants and feldspathic sandstone soil in a region of Inner Mongolia. The bacterium were identified by 16S rDNA sequence analysis. The ability of Bacillus spp. for producing indole acetic acid (IAA), siderophores, and biofilms were tested. Greenhouse experiments were conducted to evaluate the effect of Bacillus spp. on the quality of feldspathic sandstone soil, and on the growth of alfalfa (Medicogo sativa) and perennial ryegrass (Lolium perenne).[Results] Twelve strains of Bacillus spp. were screened and had different production of IAA, siderophores, and biofilms, which belong to B. halotolerans, B. atrophaeus, B. siamensis and B. zhangzhouensis. The isolated B. halotolerans P75 was able to significantly increase the content of soil organic matter (24.7%), available phosphorus (11.9%), and available potassium (21.0%) in the sandstone compared with the non-inoculated control. Soil invertase activity (58.8%) and the number of culturable bacteria (7.4 lg CFU in 1 g soil) also significantly increased after B. halotolerans P75 inoculation. Moreover, B. halotolerans P75 significantly increased the dry weight of alfalfa and perennial ryegrass grown on the feldspathic sandstone soil by 22.3%~81.5% in comparison to those of the control.[Conclusion] Our results suggest that the B. halotolerans P75, isolated from the alfalfa roots growing in feldspathic sandstone area, can increase the fertility of feldspathic sandstone soil and promote the growth of alfalfa and ryegrass, and has great potential for the phytoremediation and improvement of feldspathic sandstone soil.