Recently　emerging　perovskite　quantum　dots　(PQDs)　with　several　excellent　optical　properties,　such　as　quantum　efficiency,　narrow　band　emission,　and　tunable　emission　wavelength,　have　promising　applications　in　solar　cells　and　light　emitting　diodes.　However,　relatively　rare　applications　of　PQDs　can　be　found　in　the　field　of　sensing,　mainly　due　to　the　very　easy　degradation　of　PQDs　upon　exposure　to　water　or　ambient　humidity.　In　this　work,　for　the　first　time　CH　3　NH　3　PbBr　3　PQDs　were　encapsulated　into　superhydrophobic　silica　aerogels　(AGs)　to　protect　PQDs　from　being　degraded　by　water.　The　synthesized　PQDs@AGs　not　only　maintain　the　strong　fluorescence　emission　activity　of　PQDs　but　also　show　excellent　stability　in　the　presence　of　water.　Additionally,　PQDs@AGs　have　abundant　pores　making　them　very　suitable　for　gas　sensing.　For　improving　sensing　performances,　3D-printing　technology　is　introduced　into　gas　cell　design　and　fabrication　for　the　first　time.　Finally,　a　novel,　sensitive,　selective,　and　reversible　fluorescence　sensor　for　SO　2　gas　based　on　the　PQDs@AGs　functional　material　and　the　3D-printed　gas　cell　has　been　developed.　Copyright　©　2019　American　Chemical　Society.