Cyclodextrins　(CDs)　found　with　inexpensive　starch　are　in　a　particular　hollow　and　truncated　cone-type　configuration.　First-principles　calculations　indicate　that　a　single　alpha-CD　can　adsorb　up　to　48　hydrogen　molecules　by　the　influence　of　the　oxygen　structures　in　the　alpha-CD＇s　hydroxyl　(-OH)　and　epoxy　functional　groups;　while　the　result　additionally　shows　that　the　gravimetric　storage　capacity　can　reach　to　9.8　wt　%.　These　results　are　helpful　for　developing　high-capacity　hydrogen-storage　materials.