A　central　composite　design　experiment　was　conducted　and　the　response　surface　methodology　was　performed　to　optimize　the　degradation　conditions　of　the　mixed　bacterial　strains　that　can　degrade　toluene　and　H2S.　Results　showed　that　the　optimum　conditions　was　as　follows:　pH　6.6,　culturing　temperature　29.4　degrees　C,　inoculation　quantity　3.0%,　additive　amount　of　toluene　3.0　mu　L,　additive　amount　of　sodium　thiosulfate　4.0g.　The　selected　bacterial　strains　under　the　optimized　conditions　created　a　good　performance　of　the　bio-trickling　filter　in　treating　toluene　and　H2S　simultaneously.　When　the　inlet　concentration　of　toluene　was　600-900　mg.m(-3),　the　toluene　removal　efficiency　(Re)　of　the　BTF　could　reach　a　stable　level　of　91.2%　and　the　corresponding　removal　loading　was　50.6g.m(-3).h(-1).　Furthermore,　the　BTF　could　tolerate　an　inlet　H2S　concentration　of　74　ppm　with　a　high　efficiency　of　95%　with　the　toluene　Re　not　affected　obviously.