ZnSO4　center　dot　7H(2)O　is　modified　by　impregnation　method　with　zeolite　matrices　(13X-zeolite　and　LTA-zeolite)　to　improve　its　hydration　performance.　Water　sorption　ability　of　composites　was　carried　out　in　a　constant　temperature　and　humidity　environment.　Composite　of　ZnSO4/13X-zeolite　showed　highest　water　sorption　(0.26　g/g)　at　75%　relative　humidity　under　45　degrees　C　air　temperature,　which　is　double　than　pure　ZnSO4　center　dot　7H(2)O.　This　is　due　to　larger　surface　area　(491　m(2)　g(-1))　and　pore　volume　(0.31　cm(3)).　Furthermore,　both　hydration　rate　and　adsorption　mass　depends　on　relative　humidity　and　hydration　temperature.　However,　if　the　air　temperature　and　the　relative　humidity　are　higher　than　45　degrees　C　and　75%　RH,　the　hydration　ability　of　the　composite　material　is　significantly　reduced.　Besides,　X-ray　measurements　of　composite　(ZnSO4/13X)　revealed　that　sorption/desorption　process,　crystallinity　and　phase　of　partially　hydrated　ZnSO4　remain　the　same,　which　enhance　the　adsorption　mass　and　enthalpy　during　the　hydration　process.