Two new diprenylated flavanones, derriflavanone and epi-derriflavanone, and two new diprenylated chalcones, laxichalcone and derrichalcone, have been isolated from the roots of Derris laxiflora. Thier structures were determined on the basis of spectral and chemical evidence. The two flavanones are an epimeric mixture which can be converted to derrichalcone under basic and acidic conditions.