The effects of brewing time on dry weight content and alpha-glucosidase inhibitory active component released from mulberry (Morus alba) tea were studied. Different tea products showed significant differences in inhibitory activity against both sucrase and maltase. The most effective enzyme inhibition was observed when 3 to 5 min brewing time was applied in tea preparation. In a Caco-2 cell culture experiment the tea reduced the liberated glucose contents in both apical and basal sides of the cell monolayers. It can be concluded that hot water extract of mulberry leaves does have inhibitory effect against alpha-glucosidases, sucrase and maltase enzymes, and has a potential to be consumed as antidiabetic herb tea.