Abstract:[Objective] The return of Trifolium repens to an apple orchard was investigated to understand the effects on soil bacteria diversity in different degradation stages, and to provide theoretical basis for the utilization of T. repens in orchards and the promotion of pasture-planting in orchards.[Methods] Fresh T. repens was covered or buried in an apple orchard in Luochuan County, Shannxi Province. At 1, 3, 6 and 12 months of T. repens degradation, soil samples were collected, and high-throughput sequencing technology was performed to determine the diversity, richness and structure of soil bacteria.[Results] ① There were no significant differences in the diversity of preponderant bacteria after T. repens returning, but some richness was different. Acidobacteria, Euryarchaeota, Crenarchaeota, Spirochaetes and Nitrospira were found in the soil of the return treatment group. ② There were some remarkable differences in community distribution of soil bacteria (p<0.05), varying in different degrading period after the return of T. repens. The richness of Acidobacteria, Bacteroidetes and Proteobacteria increased, but that of Firmicutes decreased in soil samples from the two treatment groups compared with the control. ③ Over time, the richness of Gemmatimonas, Flavobacterium, Opitutu, and Arenimonas increased in groups in which T. repens had returned; however, the richness of Nitrospira, Neisseria, Pirellula, and Steroidobacter decreased.[Conclusion] Either covering or burying T. repens could optimize structure of soil bacteria community, increase probiotics abundance and improve the matter cycle in the microbial ecosystem.