Abstract:[Objective] The role of microorganisms in feldspathic sandstone soil remediation was explored, in order to provide new ideas for the scientific assumption of microbial enhanced plant improvement of feldspathic sandstone soil.[Methods] Ryegrass was used as the test crop, and the effects of inoculating Bacillus hallotolerans P75, humic acid fertilizer and different combinations of bacterial fertilizer on soil physical and chemical properties, growth and stress resistance of ryegrass were studied by pot experiments.[Results] Compared with the control, the synergistic treatment of Bacillus hallotolerans P75 fermentation broth and humic acid significantly increased the SOD activity (229.7%), POD activity (83.6%) and proline content (119.3%) in ryegrass leaves, significantly increased the contents of polysaccharide, organic matter, available phosphorus and available potassium and significantly reduced the soil water permeability in feldspathic sandstone soil.[Conclusion] The synergistic effect of Bacillus hallotolerans P75 fermentation broth and humic acid fertilizer can significantly control the water and nutrient loss of feldspathic sandstone soil, improve the stress resistance of ryegrass, and strengthen the improvement and repair of feldspathic sandstone by plants.