This study comprehensively investigated the effects of adding Paenibacillus mucilaginosus to industrial-scale compost on compost quality, microbial community dynamics, and antibiotic resistance genes (ARGs). The results of this investigation unequivocally demonstrated that the inclusion of Paenibacillus mucilaginosus prolonged the thermophilic phase of composting, thereby enhancing organic matter decomposition and facilitating nitrogen fraction conversion. Moreover, the inoculation of Paenibacillus mucilaginosus altered the microbial community structure during the rapid heating and thermophilic stages. Significantly, the removal rates of tetM, tetR, and sul1 were 99.84%, 99.68%, and 97.61%, respectively, with inoculation increasing these rates by 8.94%, 9.85%, and 9.34%, respectively, compared to the control (P <
0.05). These findings highlighted the efficacy of incorporating Paenibacillus mucilaginosus into industrial-scale compost as a potent strategy to enhance nutrient transformation processes and mitigate ARG activity.