The　effect　of　the　magnetic　field　on　denitrification　process　in　immobilized　bacteria　particles　was　investigated　in　this　study.　The　magnetic　field　could　enhance　the　denitrification　efficiency,　especially　for　wastewater　with　low　C/N　ratios,　and　the　average　removal　efficiencies　of　NO3--N　increased　by　6.58%.　High-throughput　sequencing　analysis　revealed　that　the　magnetic　field　had　substantial　impacts　on　the　stability　of　microbial　community　structure　and　relative　abundance　in　immobilized　bacteria　particles,　which　was　beneficial　for　the　stability　of　denitrifying　bacteria.　Through　the　research　in　this　paper,　we　suggest　that　magnetic　field　can　be　used　to　improve　the　denitrification　performance　of　immobilized　bacteria　particles　in　the　wastewater　treatment　industry.