n-Butane　conversion　was　used　as　a　probe　reaction　to　investigate　the　influence　of　acidity　and　topology　of　zeolites　on　the　reaction　properties　at　low　temperatures.　The　results　show　that　the　number　of　catalytic　Bronsted　acid　sites　determines　the　reaction　rates.　The　bimolecular　pathway　of　n-butane　reaction　requires　two　adjacent　acid　sites,　while　the　monomolecular　reaction　occurs　on　the　isolated　Bronsted　sites.　The　contribution　of　bimolecular　reaction　primarily　affected　by　the　number　of　catalytic　Bronsted　sites　and　secondly　influenced　by　the　zeolite　topology.　The　zeolites　with　larger　cavity　provide　enough　space　for　the　formation　and　the　transformation　of　bulky　C-8　intermediates　in　bimolecular　pathway　and　give　rise　to　the　higher　contribution　of　bimolecular　pathway.　The　distribution　of　bimolecular　products　strongly　depends　on　the　maximum　free　sphere　diameter　of　zeolites,　while　has　no　direct　relationship　with　the　volume　of　the　zeolite　cavities.　This　can　be　explained　by　a　molecular　sieve　effect　of　zeolite　channels　on　the　diffusion　rates　of　propane,　isobutane,　and　pentane　from　cavities　to　external　surface　of　zeolites.　This　improved　understanding　of　the　molecular　sieve　effect　allows　one　to　design　and　select　appropriate　zeolites　for　a　special　reaction.