Although the quinolizidine alkaloids and flavonoids, the main active components of the traditional Chinese medicine Sophora flavescens, have been largely investigated, a new matrine alkaloid derivative 9alpha-hydroxy-7,11-dehydromatrine (1) and a rare 1,4-diazaindan-type alkaloid flavascensine (17), together with 15 known alkaloids, were isolated from S. flavescens. The structures were established on the basis of spectroscopic techniques.