In the cultivation process, the application of organic fertilizers instead of chemical fertilizers can effectively improve soil structure, soil fertility, nutrient absorption, and fruit quality. In this study, the effects of potassium fulvic acid and compound microbial inoculant in rapeseed cake fertilizer on soil bacteria in peach orchard were investigated. The results showed that the application of rapeseed cake fertilizer significantly increased the abundance of beneficial bacteria in the soil. The results of functional prediction showed that rapeseed cake fertilizer and potassium fulvic acid used in conjunction could improve nitrogen fixation and carbon sequestration rates in soil. This study can provide a theoretical basis for the application of rapeseed cake fertilizer in peach tree cultivation