H2S　(hydrogen　sulfide)　was　regarded　as　the　research　object　in　this　study.　The　removal　performance　of　two　biotrickling　filters　was　compared.　One　is　the　counter　flow　one,　a　traditional　bio-trickling　filter;　and　the　other　is　a　newly　self　designed　cross　flow　bio-trickling　filter.　A　mixed　culture　of　activated　sludge　was　used　as　bacterial　seed　and　the　bio-film　was　developed　by　culturing　the　bacterial　in　on　oxygen　bottle　using　Na2S　as　inducing　substrate.　The　cross　flow　bio-trickling　filter　can　operated　at　high　removal　efficiency　once　start　up　the　experiment.　The　counter　flow　one　needs　4　days　to　start　up.　Compared　with　the　traditional　vertical　one,　the　cross　flow　one　was　robust　enough　to　recover　quickly　after　7　days　interruption.　Moreover,　designation　of　cross　flow　could　lighten　the　packing　acidification.　The　max　elimination　capacity　of　counter　flow　bio-trickling　filter　was　170　g　H　2S/m3/h.　Cross　flow　bio-trickling　filter　achieved　the　max　elimination　capacity　of　216　g　H2S/m3/h.　©　2011　IEEE.