To　study　advanced　denitrogenation　of　low　C/N　ratio　effluent　from　municipal　wastewater　treatment　plant,　the　composite　carbon　filler　composed　of　corncob　pretreated　by　alkali,　zero-valent　iron　and　activated　carbon　was　made.　The　performance　of　composite　carbon　filler　denitrification　system　was　investigated　and　Miseq　high-throughput　was　also　applied　to　study　the　microbial　community　structures.　Composite　media　in　denitrification　could　be　effectively　used　and　achieve　a　higher　total　nitrogen　(TN)　removal　rate.　The　TN　removal　efficiency　of　the　denitrification　reactor　could　be　above　95%　and　the　concentration　of　TOC　in　the　effluent　was　about　15mg/L　when　the　temperature　was　about　28,　the　Hydraulic　Retention　Time　(HRT)　was　7.7h　and　the　inflow　NO3--N　was　about　20~30mg/L.　The　analysis　revealed　that　at　the　genus　level　the　genera　related　to　denitrifying　and　degradation　of　cellulose,　was　accounted　for　40.35%　and　29.04%　which　were　related　to　known　bacteria,　respectively.　So,　the　masses　of　denitrifying　bacteria　and　cellulolytic　bacterium　in　the　sludge　made　it　feasible　to　denitrify　of　composite　carbon　filler　efficiently.　©,　2015,　Chinese　Society　for　Environmental　Sciences.　All　right　reserved.