Using a bioactivity-guided method,two new flavanone glycosides and eight previously reported flavonoids were isolated from an aqueous ethanol (50%) extract of litchi (Litchi chinensis Sonn.) seeds.By spectroscopic methods,including 1D and 2D NMR (heteronuclear multiple quantum coherence (HMQC),heteronuclear multiple bond correlation (HMBC)) techniques and mass spectrometry,the chemical structure of the new compounds were elucidated as (2R)-pinocembrin-7-O-[(2",6"-di-O-α-L-rhamnopyranosyl)-β-D-glucopyranoside] (1),pinocembrin-7-O-(6"-O-α-L-arabinose-β-D-glucopyranoside) (2),and the eight known compounds were determined to be quercetin (3),phlorhizin (4),pinocembrin-7-O-glucoside (5),kaempferol-7-O-β-D-glucopyranoside(6),onychin (7),nairutin (8),narcissin (9) and pinocembrin-7-O-[(6"-O-β-D-glucopyranoside)-β-D-glucopyranoside) (10).Some of the isolated flavonoids were tested for their inhibitory effects on α-glucosidase; compounds 3 and 4 showed stronger inhibition than the control,acarbose.