The stem extract of Tephrosia purpurea showed antiplasmodial activity against the D6 (chloroquine sensitive) and W2 (chloroquine-resistant) strains of Plasmodium falciparum with IC50 values of 10.47 - 2.22 mg/ml and 12.06 - 2.54 mg/ml, respectively. A new prenylated flavone, named terpurinflavone, along with the known compounds lanceolatin A, ()-semiglabrin and lanceolatin B have been isolated from this extract. The new compound, terpurinflavone, showed the highest antiplasmodial activity with IC50 values of 3.12 - 0.28 mM (D6) and 6.26 - 2.66 mM (W2). The structures were determined on the basis of spectroscopic evidence.