Two series of compounds (chalcones and bis-chalcones) were designed, synthesized, and evaluated as α-glucosidase inhibitors (AGIs) with 1-deoxynojirimycin as positive control in vitro. Most of the compounds with two or four hydroxyl groups showed better inhibitory activities than 1-deoxynojirimycin towards α-glucosidase with noncompetitive mechanism. Moreover, most of the hydroxy bis-chalcones exhibit good α-glucosidase inhibitory activities in enzyme test. Inspiringly, bis-chalcones 2g (at 1 μM concentration) has stronger effect than 1-deoxynojirimycin on reducing the glucose level in HepG-2 cells (human liver cancer cell line).