The　effect　of　silica　gel　adsorbent　with　different　particle　sizes　on　the　heat　and　mass　transfer　and　the　cooling　capacity　of　the　solar　adsorption　refrigeration　system　was　experimentally　investigated.　The　system　adopted　the　silica　gel-water　as　the　work　pair　for　refrigeration.　Under　close　solar　radiation　conditions,　contrast　experiments　were　conducted　in　three　groups　of　silica　gel　particle　of　1mm,　3mm　and　5mm　in　average　diameter.　The　results　revealed　that　the　silica　gel　particle　of　the　medium　size　performed　the　best　with　both　the　highest　COP　and　tspecific　cooling　power　SCP2,　which　was　defined　by　the　whole　cycle　time.　Although　the　small　particle　size　increased　the　filling　mass　of　the　adsorbent,　it　also　caused　the　increment　of　the　mass　transfer　resistance　along　the　adsorption　bed　axis.　This　increment　of　the　mass　transfer　resistance　frustrated　the　adsorbent　near　the　bed　end　to　fully　play　the　role.　On　the　other　hand,　the　silica　gel　particle　of　the　big　size　would　deteriorate　the　heat　transfer　of　the　bed,　leading　to　longer　time　in　process　of　the　preheat　and　the　cooling　to　the　bed.　In　general,　it　was　demonstrated　that　the　particulate　diameter　of　the　adsorbent　material　was　a　significant　factor　to　impact　the　performance　of　the　solar　adsorption　refrigeration　system　and　should　be　paid　full　attention　in　engineering　design.　©　2022　Chemical　Industry　Press.　All　rights　reserved.