Hygroscopic　materials　used　in　contact　with　indoor　air　can　assist　in　dampening　the　peaks　of　relative　humidity　and　thus　moderate　the　variation　of　indoor　humidity　environment.　Considering　convective　boundary　air　layer’s　effort,　a　series　of　experiments　were　set　up　to　investigate　the　influence　of　air-flow　rate　and　orientation　on　moisture　buffering　effect　of　two　types　of　hygroscope　materials.　One　is　gypsum　plaster　mixed　up　with　different　percentage　of　microencapsulated　phase　change　material　(MPCM)　and　another　is　scallop　shell　scrum,　blending　with　phase　change　material　(PCM)　slurry.　A　large　climatic　chamber,　equipped　with　a　wall　of　fans　which　could　provide　stable　air-flow　rate　ranged　between　0　and　2.73 m/s,　was　used　to　create　a　well-controlled　experimental　environment.　The　results　showed　that　the　boosted　air-flow　rate　of　environment　could　increase　materials’　moisture　ab/desorption,　as　well　as　MBV　of　materials　in　practical　level.　In　addition,　the　differences　between　vertical　and　parallel　samples　amplified　when　air-flow　rate　raised.　Detailed　analysis　revealed　that　air-flow　rate　influenced　the　initial　absorption　stage　the　most,　considering　its　effect　on　evaporation　process.　©　2020,　Springer　Nature　Singapore　Pte　Ltd.