In this study,chemical constituents and their bioactivities of widely consumed flower buds of Sophora davidii (Franch.) Skeels(Leguminosae) in China were analyzed.Using chromatographic methods,16 compounds were isolated from ethanolic extract of flower buds of S. davidii.Their structures were identified as 9α,14β-dihydroxymatrine (1),sophoramine (2),9α-hydroxysophoramine (3),7α-hydroxysophoramine (4),sophocarpine (5),9α-hydroxysophocarpine (6),matrine (7),9α-hydroxymatrine (8),13α-hydroxymatrine (9),9α-hydroxy-7,11-dehydromatrine (10),sophoridine (11),lupanine (12),14α-hydroxylupanine (13),3,4-dimethoxybenzyl alcohol 7-O-β-D-glucopyranoside (14),2-phenylethyl-O-β-D-glucopyranoside (15),and syringaresinol-4′-O-β-D-glucopyranoside (16) through the analyses of NMR and MS spectroscopic data.Compound 1 is a new alkaloid.Compounds 3, 4,8-10,and 12-16 were obtained for the first time from the flower buds of S. davidii.The total alkaloids and matrine (7) showed weak inhibitory activities against butyrylcholinesterase,with inhibition rates of 31% and 35%.This research revealed the chemical composition from the ethanolic extract of S. davidii and their inhibition effects on the butyrylcholinesterase,which will facilitate the further exploration of natural products from S. davidii.