Two new lupin alkaloids, which are the first ester derivatives of matrine-type lupin alkaloids, (-)'14β-acetoxymatrine and (+)-14α- acetoxymatrine, were isolated from the leaves of Sophora tonkinensis along with fourteen known lupin alkaloids: 17-oxo-α-isosparteine, (-)- sophocarpine, (+)-matrine, (-)-14β-hydroxymatrine, (+)-14α-hydroxymatrine, 13,14-dehydrosophoranol (5α-hydroxysophocarpine), (+)-sophoranol, (+)-9α- hydroxymatrine, lamprolobine, (+)-5α,9α-dihydroxymatrine, (-)-baptifoline, (+)-matrine N-oxide, (+)-sophocarpine N-oxide, and (+)-sophoranol N-oxide.