Acidic　substances,　which　produced　during　chlorinated　volatile　organic　compounds,　will　corrode　the　commonly　used　packing　materials,　and　then　affect　the　removal　performance　of　biofiltration.　In　this　study,　three　biofilters　with　different　filter　bed　structure　were　established　to　treat　gaseous　chlorobenzene.　CaCO3　and　3D　matrix　material　was　added　in　filter　bed　as　pH　buffering　material　and　filter　bed　supporting　material,　respectively.　A　comprehensive　investigation　of　removal　performance,　biomass　accumulation,　microbial　community,　filter　bed　height,　voidage,　pressure　drops,　and　specific　surface　area　of　the　three　biofilters　was　compared.　The　biofilter　with　CaCO3　and　3D　matrix　material　addition　presented　stable　removal　performance　and　microbial　community,　and　greater　biomass　density　(209.9　kg　biomass/m(3)　filter　bed)　and　growth　rate　(0.033　d(-1))　were　obtained　by　using　logistic　equation.　After　200　days　operation,　the　height,　voidage,　pressure　drop,　specific　surface　area　of　the　filter　bed　consisted　of　perlite　was　27.4　cm,　0.39,　32.8　Pa/m,　974,89　m(2)/m(3)　,　while　those　of　the　filter　bed　with　CaCO3　addition　was　28.2　cm,　0.43,　21.3　Pa/m,　and　1021.03　m(2)　/m(3),　and　those　of　the　filter　bed　with　CaCO3　and　3D　matrix　material　addition　was　28.7　cm,　0.55,　17.4　Pa/m,　and　1041.60　m(2)/m(3).　All　the　results　verified　the　biofilter　with　CaCO3　and　3D　matrix　material　addition　is　capable　of　sustaining　the　long-term　performance　of　biofilters.　CaCO3　could　limit　the　changes　of　removal　efficiency,　microbial　community　and　filter　bed　structure　by　buffering　the　pH　variation.　And　3D　matrix　material　could　maintain　the　filter　bed　structure　by　supporting　the　filter　bed,　regardless　of　the　buffering　effect.　(C)　2020　Elsevier　Ltd.　All　rights　reserved.